Types Of Swimming Pool Filters

During swimming pool design, you will need to think about the kind of filtering system you want to use for your pool. Here is an overview of the three most popular filters that swimming pool construction companies will recommend- cartridge, diatomaceous earth and sand.

Cartridge filters

Cartridge filters usually use a synthetic filter material that catches the debris as it passes through the filter. They work similarly to water filters in your bathroom sink. They offer a larger area of use than sand filters and can filter particles that are 25-100 microns in size. Cartridge filters also run at a relatively low pressure which means that there is less back-pressure put on the pump. This is why cartridge filters can give you more relative turnover and flow for its pump size. The filters are cleaned by simple hosing once or twice a year.

Diatomaceous earth filters

Diatomaceous earth (DE) filters contain DE which is made up of tiny diatoms of exoskeletons that have been fossilized. They are used as the sieves in the housing of the filter that can filter out very small particles (3-5 microns). This makes them the most efficient filters in the market at the moment. The DE powder is used to coat the grids in the filter and they can handle an area smaller than cartridge filters but larger than sand filters. A rise in filter pressure can be remedied by backwashing the filter (running it in reverse) so that the dirt is pushed out and the DE powder moves in to recharge the filter. However, the DE filters need higher pressure so they offer a relative loss in turnover and flow efficiency compared to cartridge filters.

Sand filters

Sand filters work by having the dirty water run through a bed of sand through lateral pipes at the bottom of the pool. Sand filters can filter out larger particles (20-100 microns in size.) They can be backwashed like DE filters by running the filter in reverse once the pressure rises. They need to be backwashed every couple of weeks to keep them efficient. The major advantage of sand filters is that they are relatively inexpensive and the filtering sand can be replaced cheaply. However, they are best used for lightly used pools because they are not good at filtering out very small particles. 

Choosing the right filter depends on a number of factors and a swimming pool service company can help you choose the right one for your pool.