Nick Inch
3 Different Types Of Pool Filters Explained
Whether you are installing a new pool or maybe your existing pool is not staying as clean as it should; you may be considering your options for pool filters. There are 3 different types of pool filters. If you want to learn a bit about each of these filter types, you're in the right place.
The first type of pool filter and probably the most common is called a sand filter. The 2nd type of pool filter is called a cartridge filter. Finally, the 3rd type of filter is called a DE filter or Diatomaceous Earth filter. Each of these filters have pros and cons and we will discuss several points pertaining to each type of filter.
Sand filters are probably the most common type of pool filter. The way these filters work is pretty simple. The entire filter consists of a vessel, filter media, lateral assemblies and a multi-port valve. These filters are usually round and are filled with sand which is the filter media. The pool water is pumped into the top of the filter and then pulled down through the bed of sand which filters out debris and particles. At the bottom of the sand

bed there are laterals, which allow the water to pass through them, but not the sand and debris, which remain trapped inside the filter. The filtered water is then returned to the pool, clean and clear. Once the filter fills up with debris, the pressure inside the filter builds and the filter needs to be backwashed. When backwashing, the flow of water is reversed inside the filter, which washes out all the debris from the sand. However, instead of returning the water to the pool, the water is ejected through a backwash line, and pumped out of and away from the pool.
Sand filters are simple to operate and other than backwashing about once a week, they require very little maintenance. The sand should be changed about every 5-7 years, however.

Cartridge filters can look similar to sand filters. The main difference is that instead of using sand as the filter media, they use a polyester cloth, or paper filter cartridge. The water passes through the cartridge which filters away debris and particulates. The clean water is then returned to the pool. Cartridge filters don't require backwashing every week. However, at least once or twice a year, the cartridges need to be removed from the filter and cleaned either mechanically or chemically.
Finally, the last type of filter is a Diatomaceous Earth or DE filter. These filters can remove even the finest particulates and debris from pool water. The tradeoff is that they require a little more maintenance. DE filters are similar to cartridge filters, since they have a polyester type mesh or "grid" inside the filter. These "grids" are covered in a fine powder called Diatomaceous Earth which is derived from the microscopic skeletons of phytoplankton, called diatoms. The DE powder which coats the "grid" mesh actually does the filtering, and then the ultra clear water is returned to the pool. DE filters however, require a backwash about once a month which removes all the DE powder from the grids, which then needs to be replaced by adding more DE powder to the skimmer.
Additionally, DE filters need to thoroughly cleaned once or twice a year. Moreover, it can be detrimental to run a DE filter without the proper amount of DE powder coating the grids.
Hopefully, this article will help you decide on which type of filter is right for your pool. If you have any more questions about filters or want to have a new filter installed, please contact us today and we can help educate and also install your new filter as soon as possible.