Friday, July 29, 2011

Circulation continued 1.1

Now that we have covered circulation in some detail, lets summarize in a table, some of the physical attributes that will influence the circulation of a swimming pool.

Circulation = Water Flow

1. Large/small pool
2. Low/high head pump
3. Small/large diameter pipe
4. Small/large filter area
5. Suction/pressure side cleaner
6. Single/Dual skimmers
7. Long/short pipe runs
8. Convoluted/straight pipe runs

So we can start with the first category in our table, which is the size of the pool. There is a formula that states that a swimming pool should be able to have it's entire volume pass through the pump and filter within an eight hour period. If you have a 20,000 gallon pool and your pump, filter and piping have been correctly sized, then the pump should be able to draw 20,000 gallons of water from the pool and push that water through the filter and back into the pool, within that period of time. With a larger sized pool, it will be more difficult to accomplish this goal. A much larger pump, filter and pipe diameter will be necessary.

This is the very essence of the problem: When you double the width and length of a pool, you increase its total volume by four times. So if you have a pool that is 12x24 foot and that pool contains 20,000 gallons of water, an increase in size from 12x24 to 24x48 foot will give you a pool with a volume of 80,000 gallons.

Do you think that a new pool builder is going to give you four times the pump, four times the filter, and four times the pipe, in order to keep to the parameter of getting all that water (80,000 gallons) through the filter in eight hours? With few exceptions the answer is no. Unless you insist upon it, what you may end up with, if you are lucky is, twice the equipment capacity of the smaller pool. Why? Because of cost.

In fact, I have often seen large swimming pools with equipment that should have been installed on a much smaller pool. The reason for doing this is again cutting corners to keep to keep the expense of building the pool down. What does the first time pool owner know anyway? Not much. What does the second time pool owner know? They know that taking care of a pool can be a lot of work!

Here, I just have to interject an old joke that is kicked around in the swimming pool industry and that joke would be that "You only tell your enemies to buy a swimming pool!" Can I hear you laughing? If not, it is because you own a pool, and the joke appears to you as being sarcastic, and it is, for you the pool owner. Another short one that I made up is "The easiest swimming pool to take care of is none whatsoever!"

When I have told prospective pool owners, not to buy a pool, usually they can't believe their ears! I tell them that even if you use your pool regularly, when you average it out over the course of a year, you are going to swim in the pool for maybe one hour and think about and work on the pool, for two hours, maybe more. After the first, second and third years, the swimming pool's novelty has worn off and is not used as often. I believe that most pools are not used at all, unbelievable but true. There are about 250,000 pools in Maricopa County, and most are not used whatsoever.

You may be thinking "What is he saying here, not to own a pool? Well, almost but not quite. What I am going to say here is that what you want to buy is the smallest pool that you can get away with, not the biggest you can afford. What this will do is enhance the circulation of water. What you actually need is a tea cup sized swimming pool, one that has equipment that actually belongs on a much larger pool. This type of swimming pool is going to be one that is very easy to take care of. You may even get two complete pool volumes through the filter in eight hours. You may not need to vacuum this type of pool, the automatic cleaner or in-floor pop up system may clean the pool sufficiently for you. This type of swimming pool is known as a play pool.

If you really, really want or need a large pool, because you have the money for one, or you need to host a lot of social activities, be aware of the equipment sizing issues. If you are a person that has gotten stuck with a large pool with smaller equipment, the reverse of the ideal, what you are going to have to do is either remodel the pool, or if that is not possible, then double the running time of the pump, at least during the summer. This will partially offset the small equipment sizes.

To summarize: You will increase your total circulation by keeping the pool small and over sizing the installed equipment.

Thursday, July 28, 2011

Circulation

Circulation is the last classification that exists upon a corner of our imaginary Golden Triangle. It can be defined as the flow of water through the swimming pool, all of it's equipment and piping. This flow of water is generated by the swimming pool pump's high speed impeller. The impeller is designed as a type of propeller not unlike that on a power boat. Water is thereby simultaneously pulled from and pushed back into the pool.

As we move through this discussion of swimming pool circulation it may be well to remember how important circulation is to the other two categories of our Golden Triangle, namely, filtration and sanitation. Strong circulation equals good filtration, because a greater volume of water is being pushed through the filter and therefore more dirt is removed from the pool per unit of time.

Strong circulation also equals good sanitation. Manual vacuuming, as well as the results produced by suction side and pressure side automatic cleaners, are enhanced because of the stronger flow of water. The increased general turbulence also helps keep organic debris in suspension, giving chlorine or other disinfectants an additional opportunity to kill.

There are two distinct modes to this circulatory system. The fluid dynamics of the system are such that the section of the swimming pool piping system that is just prior to the pump's impeller is under a vacuum and so is called the "suction side". That section of the swimming pool piping system that is just after the pump's impeller is under pressure and is called not surprisingly the "pressure side".

Swimming pools utilizing a pump will have therefore, a suction and a pressure side to their configuration, with the front half of the pump before the impeller, remaining on the suction side and that section of the pump that is after the impeller, remaining on the pressure side. The pump's impeller is the dividing line. This is a handy way to organize our thinking about the pool as a whole. Because of the fact of there being a pressure and a suction side, any problems that may be similar structurally, will however, manifest themselves differently, depending upon which side of the pool's system of circulation they exist.

As a simple example: If a hole exists somewhere in the pipe, on the suction side of the pool, then what will be noticed during the time the pump is on, is a stream of air bubbles that are being pulled from that hole. The developing bubble stream will move towards the pump from that suction side hole and continue along into and through the impeller to the pressure side of the pump. The bubbles will then collect and coalesce inside the filter. During this time the bubble stream may be observed by the pool owner or operator passing just under a clear pump pot lid.

Once the amount of air inside the filter reaches a certain threshold, air will begin to be expelled from the filter, back into the pool, by way of again, a stream of bubbles. The air bubbles will enter the pool by way of the inlets and float up to the surface where they again integrate with the atmosphere. As long as the pool's pump is running this process continues.

However, once the pool's pump is turned off by the pool's operator, or automatically, by the time clock, another sequence of negative events may occur. The air accumulating inside the filter has been compressing, because it's on the pressure side now, (air compresses, water does not). The action of turning the pump off will suddenly decompress that air, it will then expand to it's natural volume within the filter and drive the water that was inside the filter out.

The result is that the water flow is reversed suddenly, and flows at a high speed, backwards out of the filter back into the pump. The now backwards spinning impeller sometimes even unscrews! The water flow continues backwards through the pumps strainer basket, removing debris from that basket, and continues back to the skimmer where the backwards flowing water lifts the diverter valve and skimmer basket up off of their resting places and sometimes even blows the skimmer lid off! If the skimmer basket and diverter valve are not placed back into their respective positions, then any debris that enters the skimmer housing will travel back to and fill up the small pump strainer basket, the next time the timer starts the pool pump.

But that is not the worst of it. It may be that the suction line that runs back to the pump as well as the pump itself may now be devoid of water. With air in the line now, what may happen is that the pump may not be able to prime itself ( prime = sucking air for a bit before actually pulling water into the volute). The pump needs to have a water flow to carry away excess heat generated by the bearing supporting the impeller, as well as the heat generated by the impeller itself spinning in an enclosed space. Have you ever noticed how a blender will heat up food if it is left on too long? The same principal operates here, the high spin rate of the impeller will (by friction with the air) heat up the pumps interior (volute) and will cause the pump and any attached piping to warp.

Conversely, if the hole we are talking about, exists after the pump's impeller and is therefore on the pressure side of the pool, then the following negative process will be observed. The hole which may be in the pressure side piping, fittings, pump, or filter, now emits a drip or stream of water, when the pump is on. If the hole is very small and just slowly dripping, then it may be fixed at your convenience, but if the hole is larger, then immediate repair job is in order.

Most of the time, any water leak is minor, and the pool may be down just a fraction of an inch per day or if the hole is larger perhaps several inches in a twenty four hour period. I have seen swimming pools that have been half emptied out before the time clock shut the pump motor off! If the amount of water that is lost is not more than the capability of the automatic filler to compensate, then weeks or months may pass before the pool owner or operator becomes aware of this leak. They may finally notice wet areas around the equipment, a high city water usage or notice that the stablizer (cyanuric acid) levels are extremely low.

During the period of time when the pumps motor is turned off, air will leak back into the water system due to the hole being on the pressure side, gradually emptying the pool's equipment of water again, (but now for a different reason). When the pump is turned on it may just churn the air. If the hole is in the filter, then resulting mass of air will compress, perhaps causing the same difficulties as before, blowing the divertor valve, skimmer basket, and skimmer lids off their mountings.

I do not want to describe the leak discovery method or repair process that this type of problem requires. This type of problem will be discussed in detail, in later posts covering repairs. My intention here is to just have you understand how your pools circulation is organized. That it can be divided into a suction and pressure side, and that each side has its own particular type of fluid dynamic. In the next post the circulation discussion will continue.

Wednesday, July 20, 2011

Filter Pressures - Sand and DE

High pressure, as measured by the gauge atop your filter is not a good thing. It does not represent good water flow, just the opposite: high pressure indicates increased restriction to the flow of water. When the filter's pressure is substantially higher than it was when you last backwashed,then it is time to backwash again or to perform a clean out. Sometimes, the clean pressure of a swimming pool's filter will be as low as 5 to 6 pounds per square inch (psi), other filters may range up to 20 psi or more, clean pressure. It just depends on a pool's particular configuration. The power of the pump, the size of the plumbing, the size, type of filter, the water inlet/outlet orifice size, the distance the pool is from the equipment, and any add ons like suction or pressure side cleaners, all influence the PSI as read from the filter's pressure gauge. All of these items have an impact upon what the pressure will be.

How are you to determine when the pressure has risen high enough, to cause you to backwash or clean the filter? There are several different ways of determining this. The first is when you notice that the "action" on the pool's surface is beginning to slow down, you may notice for instance that the inlet jets don't seem to be pushing the water as far as before, or perhaps the skimming action has slowed down.

Another way is to put your fingers into the suction line, at the bottom of the skimmer's housing. If your fingers feel like they are going to be snatched off your hand, then the filter can probably go without being serviced yet. If there is not much of a pull on your fingers, then its' time for servicing.

You may notice also, that your suction side or pressure side cleaner doesn't climb the walls as well as before, or starts to let dirt accumulate around the bottom of the pool. Also if you vacuum manually, you may notice that the suction has dropped off and dirt is not being pulled up into the vacuum hose as vigorously as before. Sometimes, if the filter is really plugged, any additional dirt added to it will cause the dirt to just go right on through and and back into the pool via the inlet jets, then you will see the dirt being put back into the pool.

If any of these situations develop, it is time to take a look at the filters pressure gauge. Most of the time you will see that the pressure gauge is 6 to 15 psi over what it was when the filter was clean. As the dirt, dust and debris accumulate within the filter, the pressure will increase and will be measured by the pressure guage in pounds per square psi. Generally, you will not want to wait until the pressure is really high. So don't wait too long. Over time you will learn at what psi pressure to backwash or clean your filter


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Monday, July 18, 2011

Diatomaceous Earth Filters, Disadvantages :

The first and probably greatest disadvantage to owning a pool with a DE filter is that is not trivial to maintain, in other words, as compared to a sand filter, the DE filter is a high maintenance item. This maintenance issue can be broken down and organized into the following two sections.


Maintenance issue # 1 :

Elaborate Backwashing and Recharging Techniques

The DE filter, like the sand filter, can be backwashed to clean it out. However, this backwashing effort is different. The DE filter must be backwashed three times in a row to remove most of the old DE media. You have to turn the pool pump off. Move the backwash valve into the proper position, and turn the pump back on. At this point, the water flow inside of the filter will reverse direction, washing the filter grids clean of the old DE powder. This dirty powder will then leave the filter and travel down the backwash pipe or hose and exit into a pit or perhaps the lawn.

Once the backwash water has turned clear, you turn the pump off and move the backwash valve back into it's original position. Turn the pool pump back on. The pump will now push water back into the filter and whatever old DE powder that remains in the filter will begin to collect again on the grids. Wait for five minutes, turn the pump off, move the backwash valve back into the "backwash position", and turn the pump back on. This time the water from the filter will still be dirty, but won't take as long to clear. This process needs to be repeated one more time, for a total of three backwashes. You will notice that the during the last backwash, just a little puff of dirt will exit. Whew!....But we aren't done yet!

You have to get the bag of DE powder, the one you bought at your local pool store. Oh! I forgot to tell you about that. You need to buy DE powder for this type of filter. Well, at least it is cheap. Also, pick up some good dust masks to wear while you are working with this powder.

According to your DE Filters manual and following the instructions on the reverse side of the bag of DE, you will measure out and use at least several coffee cans worth of DE powder to do what is called "recharging" the filter. Note: There is a specially made plastic scooper that holds one pound of DE powder. Pick one up at your local pool store.

This " recharging" is accomplished by mixing the prescribed number of cans of DE powder into a five gallon bucket, filled with water. With the pool pump running, take the skimmer lid off, lift out the skimmer basket, and the diverter valve. Then slowly pour this mixture into the skimmer. A shortcut that I have used is to just put the cans of DE powder, one at a time, directly into the skimmer, while the pool pump is running. Be aware that this shortcut really makes a mess, and you better be wearing the dust mask during the whole process, from start to finish, because there will a lot of dust in the air. The mixture will flow through the pools suction line, back towards and through the pump, and once again collect onto the septum of the filter grids. You now have a new and clean DE filter media for your pool water to flow through....

Unfortunately, not all of the old DE powder has gotten out of the filter! It never does. When you backwash a DE filter, there is always some left behind. You can get by with backwashing a DE filter perhaps three times over the course of a year or more, depending on the weather. After that, guess what? You have to disassemble the DE filter and clean it out by hand. Oh! Joy of Joys!

This disassembling process is quite involved and it is at this point where mere words fail. I will have to create a video and provide detailed instructions, or provide a link to a youtube video at this point. For now, just do a Google video search for cleaning out DE filters and you will probably find something to look at. I will talk about this manual clean out process in a later post.

There are a series of warnings in connection with diatomaceous earth powder, that I feel a need to talk about:

DE powder scatters like a fog when disturbed, and rises into the air with very little wind. Do not allow anyone to be close to you as you are working with this powder! As you fill your can or scooper with DE powder, the powder will float in the air around you. So be sure you are using your face mask. A lot of people, including professionals, try to get around the wearing of a dust mask. They get the bright idea to just hold their breath. I too have tried to skip wearing a dust mask. Sooner or later you will screw up and draw air filled with DE powder into your lungs. Twice, I have spent several days coughing and spitting up white DE powder. Guess what? You can't get all of this stuff out of your lungs. It stays in there for the rest of your life and fuses with your lung tissue. Use a dust mask.

Do I need to warn you against leaving the partially empty DE powder bag around where children might have access to it? Yes, I do. Put the bag high up on a shelf, preferably with a bunji cord wrapped around it. Warn your children or grandchildren to stay away from this stuff.


Maintenance issue # 2 :

Fragile Internal Frame and Grid Work

The second big disadvantage to owning a DE filter is that the internal plastic grid work, and the grid work's septum are fragile and they just don't last nearly as long as the internal parts of a sand filter. The grids, themselves, when viewed from above are designed in a spiral pattern to maximize filter area within a confined space. It is not uncommon that after as little as two years, during a clean out, you may notice a tear or a hole in the fabric of the septum of one or more of the grids. The ribs of the septum frame may also be broken. Any grids that have these defects are going to have to be replaced. Any twigs that get into a DE filter may puncture the septum, and that small puncture expands into a hole. If you neglect regular backwashing of your DE filter, the grid work will tend to break or be crushed. If you neglect cleaning out your filter, "bridging" between grids may occur, this increases the pressure on the grid frame and can break it.

So, with all of the previous information, it seems that a DE filter is a real pain, and it is. Do I still recommend this type of filter? Yes! I will still recommend a DE filter to anyone who is not afraid of learning something new, who is not afraid of getting their hands dirty or to someone who is not afraid of paying someone else to do the dirty work. It is just that a DE filter does such a very, very good job at filtering your pools water, that all the hassle is worth it. Ask anyone who owns one.

The next post will cover filter pressures.

Sunday, July 17, 2011

Diatomaceous Earth Filters - Advantages

The last filter that I want to talk about is the diatomaceous earth (DE) filter. This filter type is the filter that is going to give you the most bang for your buck. The filter media here is diatomaceous earth, whereas in the cartridge filter the media is a glorified polyester paper, in the sand filter it is the sand that is the filtering media. When a DE filter is installed, the last part of the process is to add the DE powder by way of the skimmer. This "powder" is made up of many millions of skeletons of a microscopic animal called a diatom. This powder is mined from various deposits around the world.

Diatomaceous earth powder, when introduced into the skimmer, while the pump is on, flows with the water into the filter. As the DE powder enters the filter it encounters an internal structure called the "septum". This is a cloth like plastic platform which is supported by a plastic framework. You keep adding DE to the pools skimmer as directed by the DE filters owners manual. The powder collects upon this septum to a depth of about 1/2 inch. Once the DE powder has been added to the filter it usually adheres to the septum even when the pump turns off.

When the pool pump is operating , swimming pool water will flow through this layer of DE. Through a straining process, the pool water will leave behind particles of dust, dirt and debris on the surface and the inside of this layer. The water will continue to flow through the DE and then through the septum, returning to the pool cleansed.

This DE filter media will remove particles down to 3 microns, and this it will do immediately, right from the start, no other filter can do this as quickly or as economically. You can perform the following test: At night, turn on the pool light of a pool that has a DE filter. If the filter has been running sufficiently, then as you look into the beam of light you will notice no dust, just a crystalline clarity. If you do the same with a cartridge or a sand filtered pool, you will see a lot of stuff floating around within the beam of light. This stuff just blows right on through a cartridge or sand filter, over and over again without a chance of leaving the pool.



Advantages of a Diatomaceous Earth Filter:


1. The DE filter has the ability to immediately filter out particles down to 3 microns or less.

2. Your pool will have unparalleled clarity, due to advantage number one.

3. The old filter media is completely replaced every time you backwash and recharge the DE filter.

4. Algae, if it starts to grow, gets trapped initially in the total darkness of the filter. Where
there is no light, and therefore no growth. This gives you a little time to add some more
chlorine.

5. Bacteria, if present in the pool water has much less organic debris to feed upon.

6. You will have longer cycles between backwashings, because of the larger filtering area.

DE filters come in 24, 36, and 48 square foot or larger sizes. This greater filter area means that you will not have to backwash a DE filter as often as a sand filter. Sand filters in contrast, come in 3.1, 4.8, and 6.4 square foot or larger sizes. This crimps the dirt load carrying capacity of sand filters, although it is trivial to backwash them.

I had a lady call me out to a repair call on a DE filter that I had installed about a year earlier. It was a smaller 24 square foot model. What I discovered is that she had not backwashed nor cleaned out that filter in a years time! All of the internal grids were crushed! She acknowledged that I had explained to her the maintenance procedures, and that I was available to do the work, but she explained that she just never got around to it. But, that small filter did last one year, which shows you the DE filter's dirt carrying capacity.

There is an old argument between pool professionals as to what is best to install on a pool, a sand or a DE filter, I prefer the DE filter. One professional said to me "What are you talking about? All they are going to do is swim in the pool, not drink from it!"

You know, he is correct, but lets put it this way: Which pool do you want your children or grandchildren to be swimming in? I want my grandkids to be swimming in water that has been filtered and sanitized to the greatest extent humanly possible and that is what a DE filter delivers. That is why I prefer to install DE filters. In the next post we will discuss some of the disadvantages of owning a DE filter.

Sand Filters

History:


Sand filtration has a long history, the earliest recorded use of sand filtration was around 4000 B.C., in India. During the Roman Republic and during the Roman Empire, municipal water systems used sand filtration to treat the water before it was distributed locally. More recently, in mid 19th Century London, it was noted that in the local area around water pumps where sand water filters had been installed, the prevalence of cholera decreased. This led the British government to install sand filters everywhere water was drawn. In the United States, a rapid sand filter was developed, one that could be quickly cleaned with streams of water.


The Popular Sand Filter:

Within the context of swimming pools, in Maricopa County, the sand filter is by far the most common filter used. There are several reasons for this. One, they are reasonably priced due to a simple design and construction. Two, they are end user friendly. Three, they perform well enough for its intended purpose. Four, they have a long life and five, they are very easy to clean. These advantages really add up, and make the sand filter probably the best all round filter.


Cleaning or Backwashing the Sand Filter:

When the desert dust storms begin in July, the sand filter can quickly remove the dirt, dust, and debris that blows into the pool. Once the filter is full, backwashing really is a snap: turning the pump off, move the backwash valve handle into the backwash position. Then turn the pump back on. During the backwashing process, the flow of water within the sand filter is reversed. The water now enters the filter from the bottom, flowing upward through the sand and lifting the dirt up from the interior and the surface of the sand bed. The now dirty water flows out of the sand filter into a backwash pipe of hose usually into a specially made rock pit or just onto the lawn.


During this process, keep an eye on the water exiting the backwash pipe or hose. When the water
turns from dirty to clear, you can turn the pump off, and move the backwash valve handle back into it's original filtering position. Then start up the pool pump. If you are picky, you can run your pump for a few minutes and then repeat the process and a little more dirt will come out. It doesn't get any easier than this. This procedure can be followed for years without any extra maintenance to the filter.


WARNINGS:

WARNING # 1 : Do not backwash your sand filter too often. A sand filter removes smaller and smaller particles as the filter becomes dirty - in other words it becomes a better filter when it is allowed to dirty up some. Now, here you want to keep an eye on the pressure gauge. Let the pressure build up over time, It is OK! When finally, the circulation to the pool begins to slow down, and the pressure gauge reading gets high, then backwash.

I read an article years ago about an individual who did his masters thesis dissertation on sand filters. He found that a large sand filter when coupled with a high head pump could, (when allowed to get dirty, really plugged), filter particulates down to the size of 1/4th of a micron! He stated in the article that there was a lot of 1/4th of a micron stuff in the filter he studied. This what is called micro-filtration, which will catch algae, bacteria and protozoa. So let's remember not to backwash a sand filter too often.

WARNING # 2 : The sand filter uses a special type of sand media whose grains have many sharp points. It is these points that capture the particles of dust, dirt and debris that pass by. As the years go by, these points get worn down. Then the sand will need to be replaced, but not by any old sand, it has to be sand made in a special way, exclusively for sand filtration. In other words, don't put ordinary sand in the filter, go to the local pool store and buy a few bags.

Situations where the sand grains have worn down and become rounded, will not happen for five, ten or more years. In fact, I have seen thirty year old sand filters that are still functional. You can expect a long service life from this type of filter.

WARNING # 3 : Do not under any circumstances set the sand filter to the backwash position during the vacuuming of the pool or while the suction side cleaner is running - all the smaller debris will pass through the pump strainer basket and be deposited within the sand filters laterals which are at the bottom of the filter, and any dirt exiting the laterals will be deposited at the bottom of the sand bed. This is the reverse of the intended design! It is difficult to get dirt and debris out of these two areas of the filter.

WARNING # 4 : Keep your head and arms away from the top of any filter that is starting to get water from the pump. I have seen from time to time a gate valve installed on the backwash line. Usually it was installed there by someone trying to stop a leaking backwash valve. This is a bad thing to do! I remember trying to backwash a sand filter and because there was a gate valve on the backwash line, in the closed position, as I turned on the pump, the residue air in the filter was compressed by the water, which did not have anywhere to go. Remember that air compresses, water does not. The top lid of the filter blew off about 75 feet into the air. If I had my face or hands in the area of that lid, I would have been injured. So always check to be sure that the backwash pipe is free of gate valves. Always check to be sure that all of the gate valves are open on the lines returning to the pool. Children like to turn valves. If there are any other problems downstream from the filter, the same thing can happen. Remember don't lean or reach over the top of any filter while it is filling with water. In fact, avoid leaning over a pressurized filter at any time.

After turning the pool pump on, always slowly loosen the air relief valve to allow any air trapped in the filter to escape. This valve will usually be located under the pressure gauge. When all the air has been released and water comes out of the valve, close it back up.

The next post will cover the advantages of diatomaceous earth filters.

Saturday, July 16, 2011

Cartridge Filters

The Cartridge Filter:

Construction:

Cartridge filters are made of polyester, and are shaped as a cylinder with pleats. The pleats enable the cartridge filter to have a large filtering capacity much larger than would be guessed at just by looking at its external housing. Newer models have several cartridges within the housing. These newer, multiple cartridge models have very large square footages, sometimes over five hundred square feet! Cartridge vacuum filters, oil filters, air filters, pool filters, are very similar in design.

Cleaning:

The cartridge filter itself, can be accessed usually by loosening a clamp or band clamp somewhere on the cartridge filters housing, the quickie cleaning process is just to wash the filter cartridge off with the water from a garden hose. Here you want to take your time and be sure to clean between the pleats or folds of the cartridge. Clean the base of the filter and then turn the filter upside down and wash off the top inside of the filter. You will also need to wash off the hollow interior of the filter, this is the most difficult part of the cartridge filter cleaning process. It is hard to get the dirt off the center interior portion of the cartridge. There is no way to get a good straight aim with the water hose, an extreme angle is all you get here. A proper and thorough cleaning always takes longer than a sand or diatomaceous earth filter and much longer than what one manufacturer advertised: "Cleaning is a snap!" That is B.S.

The proper way to clean a cartridge filter is to soak it in a product that is specially formulated for this task. A good soaking will help remove oils and other dirt from the cartridge's pleats that a simple rinse off will miss. After it has been soaked, then it is time to wash off the remaining dirt. It is best to have two cartridges, one that is being used and another one that has been soaked and completely rinsed and cleaned and ready to go.

Note here that a cartridge filter is only good for a certain number of cleaning cycles, when the filter structure begins to get too floppy, or when the time period between clean outs gets too short, it is probably time for a trip to your local pool store to pick up a new one.


Filtering Quality:

Cartridge filters are a poor way to filter pool water, any pool with this type of filter is always more troublesome than a pool with a sand or D.E. filter. Most manufacturers specifications suggest that cartridge filters can remove particles as small as approximately thirty microns. The higher quality more expensive cartridge filter can go down somewhat lower than this. I have never been too impressed by this type. A lot of stuff is going to fly right on through this filter.


Cost:

It is cheaper to install a cartridge filter during a renovation, or in a new pool. But after a few years, the high cost of replacing old worn out cartridges negates whatever savings you might have initially enjoyed. This combined with the fact that regular cartridge filters cannot filter out the finer dirt particles in the pool means that you are going to spend a lot of additional time and money fussing with the pool. Equipment will wear out sooner, more frequent green algae blooms will cause additional chemical expenses and the pool will always be dirtier, all this leads me here to reject cartridge filters as a viable alternative when considering filtering options.

When I was called out on a repair call and I saw that the customer had a cartridge filter, I would immediately ask the customer to replace it with a sand or D.E. filter. The cartridge type of swimming pool filter is only appropriate within an absolutely cash strapped situation. Even then, it would be best just to wait and save some money up for a better choice. They may perhaps be useful in spa situation, but even here the spa water had better be changed frequently, and a sharp eye kept on disinfectant levels and associated sanitation parameters. Spas will be covered in a later post as an aside to the main theme of this blog.

I feel justified in bluntly stating here that cartridge filters are a very poor choice when considering filtering options. There are some very high tech cartridges out in the marketplace, but these are generally very costly and still present a formidable cleaning process.

The next post will cover sand filters.

Friday, July 15, 2011

Swimming Pool Filtration

Mechanical Filtration:

Filtration of your swimming pool, could have been considered a part of the earlier cleaning process, which included vacuuming, leaf netting, emptying out of the baskets, etcetera. However, the distinction justifying the separation here, is that the mechanical filtration process, driven by water being forced through the filter, extracts particles from the water; particles that are far too numerous and far too small for any kind of manual removal. The mechanics of doing so are complex enough to warrant giving filtration it's own heading or section on the imaginary Golden Triangle.


Chemical Coagulators:

These coagulators, are products which assist in this mechanical filtration process, by causing very small dust particles, (ones that normally pass right through a filter), to "bunch up". These particles are then easily trapped by the filter and removed from the swimming pool's water. This product is used in response to cloudy water due to dust, not algae. These coagulators are available at any well stocked pool store.


Chemical filtration:

There are products in the marketplace which can cause specific minerals to precipitate (fall) out of your swimming pool's water. The residue can then be vacuumed up.



Natural Mechanical Filtration:

The "Electrically powered" mechanical filtration is not the only particle removal process occurring in your pool. Natural filtration takes place in a swimming pool, by the action of gravity pulling down on all of the dirt, dust and debris that enters the water and by the slow circulation that is driven by uneven heating of the water by sunlight. All of which, given enough time, will cause the dirt, dust and debris to end up on the walls, or floor of the pool. Which then can be removed by vacuuming or by the automatic cleaner. The same process keeps the oceans, lakes, rivers and ponds relatively clear and free of larger, heavier particles.

A friend of mine has run his pool for over two years utilizing natural filtration. He does not have a regular filter on his pool. As the bottom and walls of the pool becomes dirty, he vacuums the debris directly out of the pool. He does keep the chlorine and pH at normal levels. The pool has remained clear throughout this time. He does not swim in his pool, although he could. This is not as unusual as it seems:

In the earlier part of the last century, in the city of Los Angeles, around Hollywood, swimming pools did not have filters. What was done is to have two swimming pools, side by side, one empty although clean and one full of water and in use. When the pool that was in use became dirty, the water was transfered by a pump to the clean, empty pool. The dirty pool was cleaned up, and used again when deemed necessary. This was only possible due to the process of "natural filtration".


Unfilterable Pollutants

Water that has been naturally filtered, and purified by chemical absorption, adsorptions or by soil sediments, will present itself as either an artesian spring, or a deep aquifer. This type of water has been purified by many layers of rock, gravel, sand, and sediment, and is generally safe to drink or swim in, as long as these actions are taken soon after the water is removed from it's naturally occurring reservoir and as long as no natural or man made pollution has taken place.

Natural pollution for instance, can occur in aquifers existing in volcanic rock formations. In this instance, radioactive isotopes may be present at levels that cause real health concerns. If used for drinking, bathing or swimming, then exposure to a known carcinogen has occurred.

Arsenic is present naturally in rock formations in many areas of Arizona, but is also a residue contaminate from mining processes. Arsenic is a frequent pollutant in Arizona artesian springs, and deep aquifers. I have considered that reverse osmosis, or perhaps a water softener might be of use in removing this sort of contaminate. But, this is not an area within which I have much direct knowledge.

Arizona surface or ground water may have many types of pollutants. But, I was never very worried about drinking or swimming in water from the tap anywhere in Maricopa County, as long as the tap water I was drinking was from a combination of local well water and Verde, or Salt River water. However, once Colorado River (Central Arizona Project) water began to be introduced into the tap water, I noticed a degradation in the taste and purity of that water. The water out of the tap was much harder, with a increased level of Total Dissolved Solids.

This water, when used to fill a pool, often times could be seen to be actually green, with living algae present in the tap water! I have seen this occur in Scottsdale and Glendale tap water. Yuk. I reported this situation to the water department of each city as it occurred. The Scottsdale water department responded immediately. The Glendale water department official did not believe me. I told him to come on out and take a look for himself. All my customer's neighbors have!

This Coloradoized kind of tap water makes it much more difficult to control what is happening in your pool. You may remember from an earlier post about the negative effects of hard water and high evaporation rates. Unfortunately, there is no way to filter out these negative qualities. They can only be managed.

In the next post I will begin the discussion on individual filters types. There are three main types of swimming pool filters in use. They are the cartridge, sand and diatomaceous earth filters. The cartridge filter will be the first up.

Sunday, July 10, 2011

Party Time at Your Pool!

Swimming Pool Parties

Swimming pool parties are another situation that can negatively impact your pool's disinfection program. If you are going to host a pool party, it is going to be to your advantage to move the amount of chlorine in your pool up to 4 ppm, and lower the pH down to 7.2. At the 4 ppm level, your guests may be able to notice the slight odor of chlorine. Well, don't feel sorry for them, because by the time the party's over, most of that chlorine is going to be gone. Why?, because, they all are going to be peeing in your pool. Sorry to have to break this to you, but adults as well as children, will all use your pool as a toilet. If you don't believe me, give them some ice cold beer to drink (adults only) and just watch how often your friends get up out of the pool to use the john!

Now, don't get too upset with them. Urine is generally bacteria free. The kidneys do a good job at filtering out that stuff, and no one is going to get sick swimming through everyone else's pee. However, the pool's chlorine is going to get busy and change all that urea into a combined chlorine. Combined chlorines are compounds that are chemically similar to tear gas, compounds that after a period of time, will begin to stink and burn your eyes. Otherwise, urinating in a pool is not a big deal. Combined chlorines can be later super chlorinated out of existence.

Now poop is another matter. On average everyone carries around with them several grams of poop on their anus. Thats' a given, and unless you make all your guests use baby wipes, or force them to take a shower, (with the very socially acceptable suggestion to wash their behinds), those guests are going to have very clean bottoms by the time your pool party is over, and like I mentioned in another post or two, that poop is fifty percent bacteria.

What to do? Well, like I said before, raise your chlorine level up to 4 ppm and have the pH set at 7.2. You better test the water every hour or so also, to ensure that those values stay put. Add more chlorine if necessary. This is where I like liquid chlorine, just slowly pour a pint or so into the skimmer while the pool is running to tweak the chlorine level. The pH shouldn't need to be adjusted, if you have followed along with what was suggested in the previous posts. The other thing you can do to minimize poop problems is limiting the number of guests at your party to the smallest possible number.

In spa party situations, it is totally absurd. I would never get into a spa with a crowd of people, in fact I avoid spas altogether. With the exception of a spa that is attached to a pool, I do not believe that they can be made sanitary. The load is just too great for the related small volume of water, you are therefore, taking a glorified communal bath with friends/or strangers, without soap! Yuk! In a spa attached to a swimming pool, where there is a flow of water from the pool through the spa, things here are different. The total volume of water and disinfectant that is available for that spa is sufficient. But let's get back to pool parties.

If you are having a pool party for children and/or adults, and you notice a piece of poop floating on the surface or drifting around, you will need to have all the children and any adults leave the pool immediately. Better safe than sorry here, no one wants to hear about a child that got sick at your party! So everyone out of the pool! The pool will have to be super chlorinated for a few hours to kill off all of the resulting bacteria that is introduced into the water in this scenario. If you remember from an earlier post, this is standard operating procedure in a commercial or public swimming pool setting.


Roof Overhangs

Another negative impactor on your disinfection program: From time to time, I have come across pools that have been built either too close to the home, or have had a roof extended too far into the pool area. This is understandable, because in some backyards the usable space is limited. It may have been a couple of months since the last rain and the roof will be dirty. When the summer monsoon starts, all that dirt will be washed off into the pool. This will cause an increase in the demand for chlorine and if that chlorine is not there, a green algae bloom can occur and even if the pool remains clear, it may be unsanitary. The solution here is to put up a rain gutter along the edge of the roof, or at least along the area of the roof that is next to the pool. Due to the arid climate here in the Sonoran desert, rain gutters are not normally a part of the roof system.

This completes the sanitation portion of this blog. This sanitation section will be augmented from time to time with more text and photos. The next post will begin the filtration discussion. As you may remember, that is the the subject in the lower right hand corner of our imaginary Golden Triangle.

Saturday, July 9, 2011

Negative Impactors on Disinfection

In this post, I want to talk about some of the more unusual situations that negatively impact the action of your pool's disinfectant. You may remember that I said in an earlier post, that if you keep your pool's chlorine level at three parts per million (ppm), your pool will seldom have an algae bloom. This is because at three ppm, there is still a reserve of chlorine in your pool, a reserve that will allow for exceptional situations to occur, even ones that negatively impact the amount of existing chlorine. This way there will still be some chlorine left over to carry the pool through until the next time you can add some more. It is the same here for bromine, if you decide to use this disinfectant, you will have to keep the concentration at about twice the level, in parts per million, as you do for chlorine. So lets talk about some of the situations.

Phosphates:

High phosphate levels: Phosphate is a nutrient for algae, and when there is too much phosphate in your pool's water, you may find it difficult to keep the water clear and free from algae. Phosphates originate from many sources: bird droppings, rain runoff, agricultural fertilizers, decaying plant and animal organics, urine, and sweat.

If your pool repeatedly turns green with algae blooms, even in the presence of a rigorous disinfection program, then it is time for you to test your pool water for phosphates. Take a sample of your water to your local pool store. If it is found that your pool has a high concentration of phosphates, then also have them test your pool water for it's TDS (total dissolved solids) level too. Most likely, your water will have a high TDS reading also.

There are a couple of remedies. If it is winter, go ahead and drain the pool, and then immediately fill the pool with fresh water, you don't want to let the pool remain empty for any length of time. The second remedy is for you to use a phosphate precipitating product. This will cause the phosphates to fall out of suspension, onto the floor of the pool. Then you simply vacuum the resulting debris out of the pool. Preferably, if you can, bypass the filter, directly to waste.

If you have a pool with a multi-port valve, you can just set the dial of that valve to "waste" and the precipitate will leave the pool directly. If you don't have a multi-port valve then it still may be possible to divert the water around the filter by cutting into the pipe as it leaves the pump, and connnecting the backwash hose to this stub, and as you vacuum, the phosphate precipitate will go elsewhere instead of into your filter. Later, the pipe can be glued back together. Another option here is it install a Jandy three way valve immediately after the pump, this will give you the option to vacuum to waste whenever you want to.

Nitrates:

Nitrates are formed when nitrogen from ammonia, urine, sweat, and lawn care products combine with oxygen in the water to form nitrates, nitrates will take the oxygen out of your hypochlorous acid. This destroys the hypochlorous acid and obviously weakens your disinfection program. The solution here is to drain the pool, there is no alternative. Pool draining will be covered in a later post.

Dust Storms:

These acts of nature carry so much dirt and debris that it can completely destroy all of the chlorine in your pool! Summer dust storms are the main reason I tell prospective swimming pool owners that what they need to have is the smallest pool that they can possibly get by with, as well as the biggest pump, piping and filter that they can afford. Further more, let's go ahead a get two skimmers, a dedicated line for the automatic cleaner and design a nice oval shape for that swimming pool.

The worst situation is when the new pool owner gets saddled with a huge rectangular pool with an undersized pump, an undersized filter and undersized piping. I have noticed that large pools almost never have a corresponding increase in the size of their equipment, even though the volume of water that needs to be moved and treated, is two, three, four or more times the size of an ordinary pool.

The only way to compensate somewhat for a large pool with undersized equipment is to run the pool's pump and cleaning system much more often, perhaps even continuously during the monsoon season. The owner of this kind of large pool, at any rate, is really going to have to suffer looking at a messed up pool during most of the monsoon season, or be involved in constantly cleaning it out manually, it can get to be quite a bit of work.

The dust storms that are generated in the Phoenix area can be really huge. Just in the past week, a monster dust storm more than a mile high and 50 miles wide passed through Phoenix and most of Maricopa County. It made national and international news. You can see it on YouTube. The upshot here is that if your pool is built properly, it will be better able to take a hit from one of these monster dust storms.

If you hear about or see that a dust storm is coming in, you might as well turn the pool's pump on and add a bag of shock to the skimmer. That will help prevent your pool from greening up. If the dust storm is huge or with very high winds, then as I have said in an earlier post, you might as well turn the pool pump off, and let the dust and debris settle to the bottom of the pool before you begin any clean up efforts.

Dogs in the pool:

If you let the family dog have access to your pool, the hair from it's body will shed into the pool water, make a mess inside the skimmer and pump strainer basket, the hair will entangle itself in the pump's impeller, and any that gets into your sand filter, will likely remain there for a long time, hair doesn't backwash out easily. Mud, from the dog's paws will enter the pool and since the dog's paws will be repeatedly washed off inside the pool on the steps or love seat, the filter will get plugged up sooner. Dogs also like to urinate inside the pool. Your dog's anus will be rinsed off also.

A dog that uses the pool for it's own personal entertainment is a happy dog. The pool service professional has a different viewpoint. Everything that I have been talking about up to this point, the whole sanitation process, the cleaning and disinfection procedures, are completely negated by the swimming pool owner who thinks it's wonderful to see "little wolfie" play in the pool. Sometimes, "little wolfie" gets to play in the pool with the children, or grandchildren. A wonderful sight it is! I hope they take a lot of photos.

I will not be a party to this type of joy. If I see dog hair in my customer's pool on a regular basis, I have learned from experience, that I will probably have to let them go. Usually, they will not restrict their dog's activity. So...they will have to take care of the pool themselves, or find someone else who will. I do not want to take care of, or service a swimming pool, for the pleasure of a dog. Even if that dog is accompanied by humans. Sorry.

Of course, after I became exclusively a pool repairman, I was more than willing to fix whatever pool problems "little wolfie" was causing. But, I let the customer know what the facts were on the subject. Swimming pools in the summer are always difficult to keep sanitary under the best of conditions. Keeping your dog out of the pool is a smart thing to do. Buy your dog a large plastic pool and put it off in the corner of the yard somewhere. The dog will love it. Minimize your dog's access to your pool.

Ducks:

Ducks sometimes decide that they like a certain pool, maybe your pool. Usually, the chosen pool is surrounded by mature vegetation, giving the duck, or ducks, some cover. A swimming pool that is starting to be visited by ducks, not surprisingly, will have duck poop on it's floor, and because these birds are large, the poop will be large. Obviously, this will cause an increased need for chlorine, because poop of all kinds is about 50% bacteria. That is why those ducks need to be chased away. If these ducks are allowed to build a nest in the vegetation surrounding your pool, or somewhere nearby, they will be really difficult to get rid of.

I was called once to a home where the customer had ducks for pets, this guy thought that I should be able and willing to take him on as a customer, even though the ducks used the pool, and turned it into a green pond! Sorry, no dog pools, no duck pools. There are companies that service ponds exclusively.

If you notice duck poop in your pool and you happen to see the ducks, you are going to have try to chase them off immediately, otherwise they may get nested on your property and you may have ducklings! You may have to get used to throwing bread on the swimming pool's surface!... Quack and quack, quack!

The next post: More Negative Impactors on Disinfection

Wednesday, July 6, 2011

Total Alkalinity

Total Alkalinity (TA) as it concerns us, is composed of mostly dissolved carbon dioxide, carbonates, bicarbonates, and hydroxide. It naturally occurs in rain runoff traveling over and through rock formations containing these substances. It is of interest to us because the amount of TA in your swimming pool's water is a direct measurement of the ability of that water to hold it's pH steady.

This is known as the water's buffering capacity against pH changes. Because of the TA's composition, it has acid neutralizing abilities. The higher the amount of TA in the water, as measured in parts per million (ppm), the more resistant that water is to changes in pH. The lower the amount of TA in the water, the less resistant that water is to pH changes.

If the TA of your pool's water measures between 80 and 120 ppm, your pool's water is in a state where if you add some acid, the pH will move down somewhat, and if you add some soda ash, the pH will move up somewhat. This gives you the proper amount of control over your pool's pH. Between these two values, 80 ppm and 120 ppm, is where you want the TA to be.

If you test the water for TA and the result is higher than 120 ppm, then you will find it difficult to move the pH up or down, even with the addition of substantial amounts of acid or soda ash. Conversely, if you test the water and the result is lower than 80 ppm, you will find the pH will move too easily up and down with the addition of just a little acid or soda ash. This is not good because, this indicates the pH is not stable. For instance, if, after you add a little acid to your swimming pool's water, in order to move the pH from say, 7.8 to 7.2, all is not well, because after a day or two, you will be surprised to find that the pH is back up to 7.8.

It is also annoying when after you add soda ash, in an attempt to raise the pH from 7.0 to 7.6, you find that upon the next pH test, the pH is back down too low. A negative aspect to a low TA is that the water is much more corrosive to the walls and floor of the pool, no matter what they are constructed of. A low TA combined with a low pH, will degrade your pool's plaster and concrete, strip copper from the the heater, discolor the chrome guard rails, and corrode any exposed metal in the pump. With this in mind let us see what corrective measures there are.

How to Adjust Total Alkalinity:

If you find after testing your water,that your swimming pool's water has a TA above 120 ppm, then you are going to want to use the following technique to move the TA down. Turn the pool off, and after and hour or so, the water will stop moving. Take a bottle of muriatic acid, and step up onto the diving board. Pour approximately one pint of the acid into the center of the pool. If you have a small pool, use a lessor amount. If you have a large pool, still use a pint of acid and see what happens first. After you pour the acid in: DO NOT TURN THE POOL PUMP ON! You want a low pH cloud to form in the center of the pool and to remain there, this will cause some of the carbonates within the low pH cloud to gas off as carbon dioxide. This will lower your TA. You may have to repeat this process every couple of days in order to move the TA down into the desired range, be patient it may take a couple of weeks.

If you find that your swimming pool's water has a TA below 80 ppm, then you are going to want to use the following technique to move the TA upwards. Add a box of baking soda (sodium bicarbonate) wait two or three days, test the water again. Repeat if necessary, notice that both techniques are time consuming. We don't want any surprises!

Don't do as one customer did, and put twenty pounds of baking soda into the pool all at once! The baking soda caused a purple sludge to precipitate out, which came to a rest at the bottom of their pool! I asked them, why would they do that?... "Because the guy at Paddock pools told us to! It was on a computer readout!" I looked at that readout and that is what it said. It was probably a typo of some sort, I'm sure that it was meant to be two pounds. Even so, the readout should have indicated that the addition of twenty pounds of baking soda should have been done within a time frame of weeks.

I don't like to follow formulas like: "because of this reading, you have to add so much of that" I don't go for that. Depending on what the test results are: just add a little of something to get some change, and then see what happens, then if necessary add a little more. Avoid big trouble. Remember when I said that small deviations call for small corrections, and big deviations always call for big, expensive, time consuming corrections? Well, I added some extra words this time. But, always test things out on a small scale first, if you screw up its' no big deal, just a small screw up. This idea of "testing things out on a small scale, can be applied in many other areas of life.

We have been concerned with TA because of it's relationship to pH and the influence that pH has on chlorine's effectiveness. All the dots connect!

The Next post will cover the more exotic negative impactors on the disinfection process.

Tuesday, July 5, 2011

Disinfection Continued

Natural Water Hardness, High Evaporation Rates and Total Dissolved Solids:

Let's explore some of the ways that water chemistry can negatively impact and modify the efficacy of disinfectants. One of the greatest issues we have here in the Sonoran Desert is a two fold problem. The first part of the problem is that the water we have is very hard. In other words, the water here has a lot of dissolved minerals in it, the the largest being calcium carbonate. It is not uncommon for calcium carbonate to come out of Phoenix's, Scottsdale's or Glendale's water system at a concentration of 300 to 400 parts per million. In addition to this, the fact is that the evaporation rate in the Phoenix area is twelve feet a year. So the water you have had in your pool last year has evaporated away, but has left behind all the minerals that it had contained.

As the water continues to evaporate and minerals continue to concentrate, the water level is maintained by the pool owner or by means of a automatic pool leveler. So highly mineralized water continues to enter the pool do to refilling activity and distilled water continues to evaporate. How does this impact the disinfection process? Well basically, it just gradually gets really difficult for the oxidizing agent to find the organic molecules. It is as though you are trying to find a friend of yours in a crowd, the larger the crowd and the more densely packed the crowd is, the more difficult it will be for you to make contact with you friend. Hypoclorous acid, in water that is highly mineralized, just keeps bumping into other stuff instead of the organic matter.

When you have for instance, a water concentration of calcium carbonate in the range of 1000 parts per million, you can assume that the actual total amount of everything dissolved in the water is approaching 2000 parts per million or more.There is a name for this "everything dissolved", it is called Total Dissolved Solids (TDS), when your pool's TDS gets too high, the chlorines ability to do its job or function can get reduced tremendously. So high TDS levels are caused by not only the hard water being added to a pool, combined with high evaporation rates (high temperatures and low humidity), but also everything else that gets put in the pool.

This includes stuff that is supposed to be in the water, like cyanuric acid (stablizer), sodium from any liquid bleach that has been used and regular sodium chloride, if you have a chlorine generator. One the other hand, left over calcium residues from shock treatments, or glue from chlorine tablets, atomized suntan oils, dissolved plaster, copper based algaecide residues, are all examples of stuff that we don't want in the water.

I knew of a man who bought or built his swimming pool in 1963, and refused to ever drain his pool. This pool had a sand filter which he obviously did backwash, so that the full effect of his situation was allevated somewhat. I first swam in his pool in 1976, and noticed an salty taste in his pool water: because he liked to use liquid chlorine as a disinfectant. The pool as the years went by became increasingly difficult to keep clear, and every summer would turn green until he whacked it back into shape. Finally an entire summer went by without his being able to turn the pool clear.

Finally, the pool turned a solid green all year and turned into a pond. Still he was not interested in draining his pool. The last straw was when the walls of the pool turned black. I was called in and drained the pool in 2008 and performed a chlorine wash. It took me about eight hours of work, but I got the pool back in shape.

The walls of the pool were layered with calcium ion scale, that was smooth to the touch, with a light grey coloring. This was caused by extremely mineralized pool water being run at a very high pH, and by using alkaline liquid chlorine without using acid on a regular basis to adjust the pH down. The only upside to this, was that his plaster, after all these years was still in surprisingly good shape, the high pH levels and scaling evidently protected the plaster from erosion.

This was the worst example, I have ever known, of allowing the TDS to increase to the point of collapsing the sanitation effort. So, as an absolutely critical part of your sanitation effort, be sure that you drain your pool often enough. I drain my pool every winter, around Christmas, during the coldest part of the year, and am happiest if I can drain the pool out on a cold rainy day. This will protect the pool's plaster from drying out and delaminating. Pool draining techniques will be covered in a later post.

Potential Hydrogen (pH) and Chlorine Effectiveness:

Another factor that impacts disinfectant efficacy and chlorine in particular is the water's pH, potential hydrogen. We can all remember the acid/base concept. Water that has a high pH, is base. Water that has a low pH, is acidic. The pH of your pools water is directly related to chlorine effectiveness.

When you pour liquid chlorine into the pool or introduce a granular chlorine or put chlorine tablets in the pool, chlorine breaks into two separate chemical forms. The first is called hypoclorous acid. Hypochlorous acid is the actual oxidizing agent that destroys organic matter in your pool. The other chemical that forms is hypoclorite ion. Hypochlorite ion does not oxidize organic material in any appreciable amount. These two forms of chlorine exist simultaneously in the water, one does the disinfecting, the other just acts as a type of reservoir for the hypoclorous acid.

The next idea is where you are going to learn to get interested in your pools pH. There is a direct relationship between the amount of hypchlorus acid and hypochlorite ion and the pH of your pools water. The higher your pool water's pH is, the less there is of hypochlorous acid in the water and the more there is of hypochlorite ion.

Remember we said that hypochlorous acid was the actual oxidixing agent? So if you run your pool with a high pH, no matter how much chlorine you put in the water, the killing ability of that chlorine is going to be diminished. Conversely, if you keep your pool's pH low, you will increase the amount of hypochlorite ion in the pools water, and it would appear that is what we want.

But things are a little more complicated than that. Like I stated previously, the quanity of the hypochlorite ion in your pool acts as a kind of reserve for hypoclorous acid, sort of a type of storage repository. As the hypoclorous acid gets used up, more is automatically made from the hypochlorite ion. If you run the pools pH down too low the amount of measured chlorine in your pool will disappear rather quickly, because hypochlorous acid is unstable and tends to gas off into the atmosphere, Hypochlorite ion in contrast is more stable, but unfortunately is not a very good disinfectant.

So the answer here is a type of compromise, where you keep the pH down but not too low. Most experts recommend keeping the pH between 7.2 and 7.6. This range will give you a sufficient amount of hypoclorous acid while also keeping a healthy reserve of hypoclorous acid in the form of hypochlorite ion. An additional benefit that accrues to you is this: by keeping the pools water to within this pH range, the minerals remain somewhat sequestered or held in the water instead of precipitating out in the form of scale onto your pools surfaces. If you let the pH move up for any extended period of time you may begin to notice that your plaster, whether it is white or black, will start to stain up. If you don't have a plaster pool, you will still accumulate staining on whatever surface you have and will have staining occurring around the pool's water line. So by keeping the pH lower you suppress two problems at once; you enhance the chlorines ability to disinfect your pool and you keep problem staining at bay.

How to adjust the pH:

When we want to lower the pH of our swimming pool's water, the proper method is to walk the acid, this is done by pouring the acid into the pool as you are walking along the perimeter of the pool. You want to have the pool pump running. As you are pouring the acid in, lean down towards the water in order to reduce the splashing of acid onto the cool deck, your skin or clothing. Sometimes the splashing of the acid can reach up to your face. So it would be a good idea to wear goggles.

The best method is to get down on your knees, and while holding onto the bottle of acid, let it float in the pool water near an water inlet and slowly pour the acid into the stream of water from that inlet. Never pour more than a pint of acid into the pool at one time. Wait a day then test the pH again then add more if needed. Oftentimes, it is only necessary to add a much smaller amount than a pint. Never pour acid onto your steps, or love seat areas, it will ruin the surface over time. Don't pour acid into just one area, will reduce the total alkalinity of the water. In the next post we will cover a situation where that is exactly what you want to do, and there will be a particular reason for pouring it into the water in that way.

Next, I am going to discuss total alkalinity and how it relates to the water's pH.

Saturday, July 2, 2011

Disinfection

Disinfection is the second subsection in the sanitation concept that sits atop our Golden Triangle. Here, we cannot talk about sterilization of pool water, as a sterile pool is not possible in reality. Dirt, dust, debris, organic and inorganic are always entering the your pool and there is a lag time, a latency period whereby for a certain period of time, microscopic life; a virus, bacterium, protozoa, or algae will still be alive.... even in the presence of swimming pool water that has been properly treated with chemicals, properly filtered, and one that has the proper circulation.

For instance: there is type of bacteria (Coliphage) that comes in human feces, one that is very resistant to normal concentrations of various disinfectants. This bacteria is one of the "bad" ones that can make you very sick. Because of this, lifeguards are required to shut down a commercial pool immediately upon sighting a piece of poop. After closing the pool the water must be super chlorinated for several hours. This bacteria is that tough! However, all forms of microscopic life have a certain amount of resistance to disinfectants, they don't die instantly! So... don't you drink pool water! Don't let your children drink pool water! Teach them to keep their mouths closed, and have them use nose clips and eye goggles. If I seem a little fussy here, remember how painful an ear infection, or an eye infection can be for a child or you! Certain skin conditions can arise also, but these aren't as critical. Check out this harmful bacteria chart: http://natsci.edgewood.edu/wingra/wingra_bacteria.htm

When we begin to talk about pool disinfection, it is obvious that disinfection is dependent upon and related to filtration and circulation. But at this point, I want to talk about which chemicals are going to be used to disinfect your swimming pool water, and not get side tracked into exploring these other relationships as of yet.

Chlorine is the chemical that is usually used to disinfect a swimming pool. The actual process that chlorine uses to disinfect water is called oxidation (the loss of electrons) and this is the same chemical process that you see when wood is burning or a piece of metal is rusting. It is this oxidation process that kills bacteria, viruses, protozoa, algae, and fungi.

Now would be a good time to describe the measuring protocols, or conventions, for water borne contaminates: dissolved and undissolved, organic and inorganic, mineral and chemical. All water except distilled, naturally contains these foreign substances. The concentration of these substances are measured in parts per million, parts per billion, or even parts per trillion. This is the generally accepted way of measuring "how much of anything is in water". Water test kits use this type of protocol. For instance: a chlorine test vial will have a color comparison chart that reads 1,2, or 3 parts per million.

Chlorine is the most commonly used chemical in swimming pools for disinfection. Chlorine is a member of the halogen family of chemicals, with bromine, iodine, fluorine and astatine finishing out the list. They are unique in that this particular periodic table group can exist as a gas, liquid, or solid on the earth's surface.

Iodine is used in swimming pools as an disinfectant when the swimmer, or swimmers have developed a sensitivity to chlorine. The main problem with iodine is that it turns the your pretty blue water, brown. Bromine is used sometimes in indoor pools when the smell of chlorine is intolerable due to ventilation issues. Bromine has a much heavier molecule than chlorine and so it tends to stay in the water and does not gas off as quickly as chlorine and so the odor from bromine is minimal.

Also, bromine is used therefore, in hot water applications such as spas and hot tubs. Chlorine, if used in spas and hot tubs, quickly becomes very annoying to you. When the spas blowers and jets are turned on, all your natural excitement, caused the bubbling and churning of the water, turns into a blue funk as soon as the chlorine begins to gas off, stinking up the area. They used chlorine gas in World War One after all! So don't use chlorine in your spa! Bromine in contrast to chlorine, will be barely detectable at all in the same exact situation.

Another negative quality that chlorine has is that once the chlorine has oxidized some organic material it becomes chemically changed into a compound that is not unlike tear gas! This changed chlorine is known as a "combined chlorine" or as a chloramine. Check out Wikipedia's article: (http://en.wikipedia.org/wiki/Chloramine). Chloramines are an unavoidable consequence of oxidation or the disinfection process. Chloramine is a very poor disinfectant. For example: ordinary table salt (sodium chloride) is a combined chlorine and we know that despite the fact that ocean water is salty, it would be some kind of joke to say that it has a minimal effect on the creatures that live there! Since it is actually absolutely necessary for their existence! Now, you and I know that if you increase the salt concentration above a certain threshold, as it is in the Great Salt Lake or the Dead Sea, then that will create an unlivable environment for all but the hardiest of creatures. Likewise, chloramines if allowed to increase past a certain level in pool water will cause eye, nose and skin irritation and will have an unpleasant odor. The solution to high chloramine levels is to super chlorinate or "shock" the pool in a very precise way, which will be covered in a later post.

This discussion about chloramine is leading up to the second positive attribute that bromine has over chlorine. That attribute is that once bromine has done it's job and a certain amount of bromine has been changed into a combined bromine, the combined bromine, unlike the combined chlorine, is still a effective disinfectant, and does not stink! So you get double duty from bromine!

So why is not bromine used in swimming pools instead of chlorine? Well, unfortunately, there is a real downside to using bromine as an disinfectant and that is bromine costs about twice as much as chlorine on a pound for pound basis. Although, in a spa or hot tub, the cost difference is negligible, in a swimming pool it becomes a real problem.

The next post will continue on with the positive and negative modifiers of disinfectant efficacy.

Thursday, June 23, 2011

Non-Automatic Cleaning or Get Outside and Vacuum the Pool!

Vacuuming is the most boring part of swimming pool maintenance, and yet one that needs to be done from time to time even if you have an automatic cleaner. In the Sonoran Desert, during the so called summer monsoon season, dust storms can arrive every evening. Sometimes, several developing thunderheads are scattered around. Each one will send out a dust storm. Sometimes these thunderheads coalesce into one huge monster of a storm. These will just trash your pool up way beyond the load capacity of your automatic cleaner. There is no commercially available cleaner that can take kind of load. So that is why all pool owners and pool service professionals need to have vacuuming and netting equipment.

As these storms begin to occur, there is really no way to know just how severe they will become. So I would recommend that the swimming pool be turned on if it is not already running. If you have followed my blog posts from the beginning you know that I prefer to have the time clock set to run the pool in the evening hours anyway. If the storm becomes really severe however, you might as well just turn the pool off, since the skimmer, the main drain, and the automatic cleaner will all probably get plugged up with debris. No one likes to repeatedly empty out the skimmer basket, or the automatic cleaner while it is lightning and thundering! In this case, commonsense tells you to just let the debris in the pool accumulate and then settle to the bottom of the pool over night. You can get to work, in the morning !

The swimming pool cleaning sequence that you want to follow here is basically the same for a pool that is lightly or heavily trashed up. It's just that it will take much longer to complete the cleaning with a trashed pool.

The first step is to turn the pool on at the time clock, then walk over to the skimmer and remove the lid. Look into the skimmer basket. Always look first to be sure a critter of some sort is not in the basket area. Reach down and lift out the basket, it probably would be a good idea to wear some latex gloves while you are doing this. I have seen people fashion a wire clothes hanger as a hooking tool to lift out the basket, you can try that if you wish. Clean the basket out by tapping it on a fence or large rock and if necessary, rinse it out with a garden hose. Check the basket visually to see if there are any holes or cracks in it, if so, then go ahead and buy a new one.

Next, remove the diverter valve, look to it's underside to be sure that the flap is in place, check also that the float is moving freely. At this point, I usually put my fingers down into the skimmer and let the suction line pull on them, just to get a good reading on whats going on with the upstream equipment. If it feels like the suction line is going to pull my fingers off, then the pump and filter are probably OK. Replace the diverter valve, be sure that it sets flat against the o-ring on the bottom of the skimmer housing. Now put the skimmer basket back into place. Look to see that the weir is moving freely and that it is in it's proper place. Remember to look first before you put your hand into the weir area!

If you did the "fingers in the suction pipe test" you already know that things are OK upstream. If you didn't do that test, then you can check now to see that the action of the skimmer is good. You should be able to see a very good flow into it. If there is not a good flow of water into the skimmer, or if the suction in the "the fingers in the suction pipe test" felt weak, then the pump strainer basket may be full, or the filter needs to be backwashed, or if it is a DE filter it may need to be manually cleaned out, or a host of other problems may be the culprit. But for now, put the lid back on the skimmer and walk over to the equipment area and turn the pump motor off.

Unscrew the lid to the pump strainer basket housing, it may be tight. If you are using your hands, try turning it very slowly with steadily increasing force. If it is stuck, you can buy a pump lid wrench removal tool. The one I like is the metal one with a rectangular loop that fits around most lids. With the lid wrench, you still will use the "turning very slowly with steadily increasing force" technique. When you get the lid off, check that the rubber o-ring that it rests against is in good shape. Often there is a sticky goo that forms on this o-ring or in the groove within which it fits. Either of which may cause an suction side air leak, causing the pump to lose it's ability to pull the water from the pool. You can wipe the goo off with a warm, wet wash cloth or rag. If after the goo is wiped off, a lot of rubberized dirt comes off the 0-ring onto the wash cloth, then the o-ring is worn also, replace it with a new one. The next time you are in your local pool store go ahead and pick up a tube of Magic Lube, this is the lubricant that you want to put on the o-ring and the groove that it fits into. Accept no substitutes here, if the pool store doesn't have it, go to another one. Lubricate the o-ring, the groove that it sits in, and the screw like threads on the plastic lid.

Most newer pumps have "see through" plastic lids that enable you to look into the pump strainer basket to judge how full it is. From time to time check that this lid has not developed a crack that again may be letting air into the system, these can be difficult to see. Sometimes, there is a hole or crack in the pump basket housing area with the same negative result.

Lift out the pump strainer basket by grasping the metal wire handle and turning the basket while it is still in the pump. There will be two notches on the plastic basket that will line up with slots inside the pumps basket housing. Once you have the basket lined up, you can simply pull the basket out. If the handle is missing, or the basket warped, replace the basket. As I have said before, it makes this job a lot easier if you buy a second basket so you can let one basket dry out, and later easily dump the contents. Either way, inspect the pump strainer basket for cracks or holes, replace the basket if necessary.

[Whenever I have had a service call or repair call where the problem is that the pump's impeller is plugged, I immediately know that there is a good chance that the pump strainer basket or the skimmer basket probably has a hole or crack in it. Sometimes the service person or home owner did not take the time to see that the pump strainer basket was properly seated. In this situation also many times it is the skimmer basket that has not been seated properly or sometimes the skimmer basket begins to float when the pump is off, and when the next pump cycle starts up, it is pulled down by the water flow and rests cock-eyed letting debris to get around it. The solution for a floating skimmer basket is to replace it with one that is weighted at the bottom. I have often put a rock in the bottom of the skimmer basket to weight it down. Just be sure that the rock you use is much bigger than the diameter of the suction pipe at the bottom of the skimmer housing].

Now, put the pump strainer basket back in and don't forget to put the o-ring back in! I have several times been called out to a repair call where the only problem was that the pump lid o-ring was not put back in! Screw the lid back on. Do not bear down with a lot of force while screwing the lid back on! When lubricated properly, a hand tightened lid is sufficient. If you use your new lid wrench to do this, then you are going to be forced to use the lid wrench the next time you want to take the lid off. Turn the pool pump back on. Most modern pumps will suck air from the line going back to the skimmer in order to start the water flowing again. If the pump doesn't pull up the water, or if you don't have a modern pump, you may need to prime the pump at this point by pouring water into the pump basket area before putting the lid back on and starting the pump.

Once both the skimmer basket and the pump strainer basket have been serviced, and the water flow has started again, you will want to let some of the air that accumulates at the inside top of the filter out. So it is time to look at the pressure gauge that rests on top of the filter. There should be a small valve that you can turn to open. This valve is known a an air relief valve. If you open this valve, the air will begin to be released, followed later by water. Once the water shows up the air is obviously out of the filter and you can close the air relief valve. If this valve is stuck, then you can use some WD-40 and a small pair of pliers to work it loose. Be careful here. These valves are fragile. Use minimal force.

If your pool is really trashed up, and you own a sand filter or a cartridge filter, then you are going to want to backwash, or clean the the filter before you begin to vacuum. If you own a DE filter then you may need only to note the pressure as indicated on the pressure gauge, and later decide (after noting the resulting pressure increase), whether a backwash or clean out is necessary. In a later post having to do with filtration this step will be covered in much more detail.

For now however, walk back to the swimming pool, and while the pool pump is running, use your leaf bag to net out most of the surface debris. This in itself can be quite laborious, (remember to use the technique I talked about in an earlier post). If the pool bottom is really trashed then clean out the bottom of pool with the Jandy Leaf Master and then later when the dirt and dust have settled back down you can vacuum.

If the pool's bottom does not have a lot of debris, then you can prepare to vacuum. Bring out and begin to assemble the vacuum equipment. The vacuum hose, as well as the vacuum head should have been stored out of the reach of sunlight. The vacuum hose should have been stored in a circular pattern, to facilitate the assembling and vacuuming process.

While holding on to the part of the vacuum hose that is going to be attached to the vacuum head, push the rest of the hose (which should still have the stored circular shape) into the pool. Attach the vacuum hose to the vacuum head, then attach the pool pole to the vacuum head. Then push the vacuum head with the pool pole attached, into the deep end of the pool. While still loosely holding on, let the vacuum hose slide through your hand, feeding it from the remaining circular shape floating on the pool's surface, thereby dropping the vacuum head and the pole to the bottom of the pool. This will pull the vacuum hose down also. The vacuum hose should now be filled partially with water, and you, kneeling along side the pool, can push the yet unfilled portion of the vacuum hose directly downward into the water. When you have pushed the vacuum hose all the way in, water should start to come out of the end of the hose. (This is an advance technique, which again will be covered in a later post), an alternative technique is to fill the remaining empty vacuum hose with water by placing it up against an inlet jet. You need to fill the vacuum hose completely in one way or another so as to minimize the amount of air that will be introduced into the pump.

At this point, after the vacuum hose is filled with water, drag the end of the vacuum hose over to the skimmer, kneel down and put the hose into the suction pipe that leads back to the pump. You have a choice here, you can either put the vacuum hose over the deck and then into the skimmer suction pipe or you can put it in through the front of the skimmer, laying the vacuum hose on top of the weir. Even when you have done everything correctly, there is still always some air that is unavoidably introduced into the suction pipe. Wait until it has cleared the pump, then you are ready to begin to vacuum.

Use the pole to pull the vacuum head out of the deep end of the pool and start vacuuming the steps in the shallow end. This accomplishes two things. One, by starting in the shallow end and gradually moving to the deep end, the vacuum head is going to be much easier to handle. After all, you are going to be going downhill, (gravity here is our friend once again). Do you want to start vacuuming in the deep end and try to move that heavy vacuum head uphill? I think not.

Two, you want to save the worst of the debris and dirt for last, otherwise the suction for the whole job is going to be diminished, and where is that pile of dirt likely to be? Yup! At the bottom of the pool, so don't vacuum there first. So always start your vacuuming job in the shallow end of your pool.

This vacuuming process can be facilitated by the use of a swiveling type of connector that maybe already attached to your vacuum head. You can buy a vacuum head with or without a swivel connector. If you buy a vacuum head with a swivel connector then you can steer the vacuum head by twisting the pole as you move the vacuum head forwards or backwards.

If you purchase the type of vacuum head without a swivel connector, you can still move it over easily by using the following technique: As you push the vacuum head forward and you reach the other side of the pool, you will need to move it over to pick up more dirt. The best way to do this is to snap the pole back towards you, lifting the vacuum head momentarily off the floor of the pool, as it is still suspended, snap the pole in the direction opposite to where you want the vacuum head to go. The pole will act as a lever, with the fulcrum in the middle. In other words, if you snap the pole to your left, then the vacuum head will move to the right and if you snap the pole to your right, then the vacuum head will move to the left. Again, this needs to be done while the vacuum head is momentarily suspended. After you have drawn the vacuum head all the way back so that it is nearly under you, go ahead and lift it up slowly to clean the wall of the pool, then move it over to start again. Continue until the pool is cleaned.

You may have to clean the pump strainer basket out, backwash, and vacuum several times before the pool is cleaned up. This process will cause some of the dirt and dust to be suspended into the water again. Wait for a day or so, until the dust and dirt have again settled to the bottom of the pool and repeat the process, or begin to use your automatic cleaner.

This completes the cleaning subsection of the sanitation classification, that rests upon the top of our imaginary Golden Triangle. In the next post, we will consider the other subsection of sanitation which is disinfection.

Wednesday, June 22, 2011

Automatic Cleaners, Continued

Pressure Side Cleaners


A pressure side cleaner uses either water provided by the pool pump or a smaller booster pump to move about and accomplish it's job.


Arneson Pool Sweep

One of the first pressure side systems that I knew of was called an Arneson Pool Sweep. Anthony Pools in the 1960's and 1970's used this pool cleaner almost exclusively in the pools they built. This cleaner had a floating water propelled head to which several tentacle-like plastic tubes dangled down onto the floor of the pool, which in turn stirred up the dirt on the bottom of the pool, it did clean the pool to a degree, but not as well as the Master Pool system.


Jandy Porpoise

Another pressure side cleaner that was popular during the 1980's and early 1990's was the Jandy Porpoise, this device was usually driven by a ½ horsepower booster pump. This device was attached to a long hose that ran back to a fitting on the side of the pool. This cleaner had the fastest underwater speed of any automatic cleaner, it did indeed move around the pool like a porpoise. A stream of water came out the back of the device to propel it forward. There was a short whip attached, as well as jetted connectors placed every three feet, to hold the sections of the trailing feed hose together, and help stir up the dirt and debris, unfortunately for all of it's high speed activity, it did not do a very good job, but was better than nothing. Because of it's high rate of speed, the outer edges and head ball wore down quickly. Jandy did make a version of the Porpoise that did not have a booster pump, it ran by having a valve just after the pool pump, diverting unfiltered water to the cleaner. This type of Jandy cleaner never had enough pressure to work properly, and just put dirty water back into the pool, like the Paddock Pool's pop-up system did earlier.

A lot of my customers enjoyed watching the Jandy Porpoise move around the pool, and resisted my attempts to change them over to the best pressure side cleaner, the Polaris cleaner.


Polaris

The Polaris line of pressure side cleaners were the first pressure side cleaner that really made a noticeable difference as far as saving time and effort for the pool owner or service professional. Of all the pools that I had on my service route , the pools that I had been able to convert over to the Polaris pressure side cleaner, were always in good shape when I showed up and almost never needed to be vacuumed! Let me tell you I was really happy with that cleaner!

However, even this cleaner had some downsides. It was really finicky to set up. It was driven by a jet of water turning a water wheel type of turbine located near the center of the device. This jet of water picked dirt and debris up off of the pool's floor and deposited it into a net type bag on top of the device. It also had a rear facing jet as well, with three large wheels that were driven by the turbine.

As I have stated before, one of the problems with this cleaner was that was really finicky to initially set up. Getting everything balanced just right so it could climb walls was a pain. There was a float attached that had to be adjusted forward and backward to keep the nose of the device down, otherwise it liked to move forward with it's nose in the upward position.

There was also an adjustable rear jet that had be set just so, in order for the Polaris to be able to climb out of the deep end of the pool, if this jet was not pointing in the right direction then it would make continuous circles and never climb out. Annoyingly, customers would often make their own adjustments, throwing everything out of whack.

Another big problem with the Polaris was the tail whip, in order for it to be able to swing back and forth to deliver a sufficient jet of water to stir up dirt, the tail whip had to be fed a certain amount of water, as the cleaner climbed to the top of the pool wall and reached the line of tile, it would turn itself over to go back down into the pool, spraying water simultaneously into the air, from the tail whip, often times getting the decks wet as well as windows, and Arcadia doors. Sometimes, customers or I would be standing alongside the pool and be startled by the squirt. Polaris tried to address that problem by making a weight for that tail whip, but that slowed down the cleaning action tremendously, I never really found a solution to that problem. The best I could do is to never install a Polaris in a pool that was too close to the house.



Suction Side Cleaners


Kreepy Krauly

The Kreepy Krauly was the first automatic suction side cleaner. It was developed in 1974 by a South African father and son team, an hydraulics engineer by the name of Ferdinand Chauvier and his son, Daniel. Several million of these Kreepys have been sold internationally, Ferdinand Chauvier died in 1985. His son Daniel sold the company to PacFab which later became Pentair Pool Products.

When I saw this device for the first time I thought that it looked like some science fiction, alien type of life form. It still looks weird to me, and the name fits. Kreepy Krauly. The device moves about driven forward by a diaphragm that momentarily shuts of all the water that is flowing through it and snapping or perhaps vibrating the device forward, it does this more than several times a second. This device is big, noisy and ugly, but it does clean a pool and it has only one moving part! However, it will not clean steps, or the love seat area. At times, it will get stuck in a corner, wedge itself somewhere, or it will sometimes adhere to a wall that is uneven. When it adheres to a wall, the pump may be starved for water unless a special valve has been installed at the skimmer.

This cleaner has a very bad habit of wanting to come out and above the pool surface to start sucking air, and then not wanting to go back down until the whole hose and pipe running back to the pump is full of air! Once the pump loses its water, then the device sinks back into the pool, and the poor pump churns away trying to pull water from that great distance. Sometimes, it fails to draw water and overheats. At a minimum, there will be distortions in the pump housing or suction side piping causing air suction leaks. So the upshot here is that this is a cleaner that works, however, it will need to be continuously monitored when in use.

Not many pool service professionals install this type cleaner because of the headaches that come along with it. It is just too unwieldy. The majority of these devices are purchased by the pool owners themselves and just placed in the skimmer. My customers from time to time have purchased this cleaner without consulting me. I have had to ask them to take it back. If they refuse, I list for them the problems that will occur. If they still insist on keeping the device I had to let them go. Sometimes, the skimmer is shut down permanently by the customers action, and the pool owners neglect to remove the device once the cleaning job is finished. There are plastic covers that have been developed that cover the skimmer basket to which the 'Kreepy” can be attached, whereby the flow rate from either the Kreepy or the skimmer can be regulated, but they are not commonly seen and don't work very well.

I have complained to the Kreepy Krauly field representative about the device slowing down or stopping the skimming action altogether due to regularly improper installation by pool owners and received the retort: “Well you can't have everything! Which segways into my biggest gripe about all suction side cleaners and that is that they slow down the total circulation of the swimming pool. When you ask the pool pump to drive one of these devices that is the result.

The work around has been to install a dedicated line for these devices that runs back to the pool pump. By installing a Jandy 3-Way valve just in front of the pool's pump, you can easily control the amount of water that is coming from the suction side cleaner and how much water is coming from the skimmer. You can if you wish, turn the skimmer completely off and have all the water pulled from the cleaner or completely shut off the cleaner and have all the water pulled from the skimmer. This is a workable solution for all the suction side cleaners.


Hayward Pool Vac

The other suction side cleaner that I am going to talk about is the Hayward Pool Vac, originally called the Arneson Pool Vac. This is the best of the suction side pool cleaners. It is driven by a turbine located near the center of the device, just above the intake orifice. As the turbine spins the internal mechanism drives toggling foot pads or pods that rock back and forth very quickly and enable the device to move forward. Assuming that you have enough suction from your pump this device really cleans up the pool nicely. I always liked to install a in-line leaf canister with this cleaner, since doing that increased it's ability to clean up a really messy pool. If this device is installed on a pool that has a strong pump and if that pool has a dedicated line for the Hayward Pool Vac, I do not have any reservations in recommending this cleaner. Just be sure to install a in-line leaf canister to catch the leaves and debris before thy get to the pump.

Some things to be aware of here is that small rocks can be sucked up by the Hayward Pool Vac, either plugging or jamming up the turbine. So if the cleaner suddenly stops working, that is the first place you want to look. Also,(and this goes for all the suction side cleaners), if the cleaner stops working or seems to have not a lot of energy, check the hose line for cracks or tears, the pump maybe pulling water from these holes instead of the cleaner.

Also the pipe running back to the pump may have become plugged with debris, this happens frequently when any suction side cleaner is used without a leaf canister attached. What happens in this case is that a twig or something similar gets stuck in the pipe inside of a pipe elbow and then smaller more pliable debris begin to wrap themselves around the twig or more rigid obstruction. This will continue until the flow to the pump has ceased.

I remember one time I got a call from a pool owner who already had a rotor rooter guy out who tried to clear out the skimmer line- to no avail. I brought my tank of carbon dioxide gas to blow out the line. As I blew out the line, quite a bit of garbage came out, but it wasn't completely clear. So, the customer and I resorted to using a toilet plunger, we took turns with it and after a few minutes, out pops a small toy car. It just goes to show you that sometimes a low tech solution works! That was the first and last time I had to use a toilet plunger on a swimming pool!

One last word on suction side cleaners: WARNING: Do not use your cleaner to clean a clean pool! Whew! In other words, don't run the cleaner all of the time. Just run it when the pool is dirty. It won't wear out as quickly.



Robotic Cleaners

Robotic cleaners are the newest thing on the market as far as automatic cleaners are concerned. They are driven by household current that has been converted to low voltage. Because these robotic cleaners have their own built-in filter, the use of the primary filter is reduced. If the pool pump is turned off, and after several hours, any suspended dirt particulates will have settled to the bottom of the pool, and then when the robotic cleaner is turned back on, the effect is enhanced and the primary filter's usage will be reduced further. These cleaners are able to be adjusted so that they can clean tile too.

Some of the robotic cleaners can be steered from poolside controls. The only downside here that I can see is that these cleaners are very expensive, up to $1400. The last point to remember here is that you can't avoid some work when you use any of these automatic cleaners. You will still need to clean and service the cleaner.