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.