Swimming Pool Store

Swimming pool filters are an essential part of having a safe, clean swimming pool, but many consumers are unsure of the best type of pool filter.  There are three basic types of filters and each has its own positive and negative characteristics.  The three types are sand filters, cartridge filters, and diatomaceous earth (or DE) filters.  Here are descriptions of the three kinds of pool filters and some advice for choosing the one that would be best in your particular situation.

Sand filters are tried and true and usually the least expensive of the three types.  They work by pumping the pool water down through sand, which strains out particles of debris.  The clean water drains out the bottom and returns to the pool.  Of the three types of filters, sand swimming pool filters are the least effective at cleaning the water.  Another drawback with them is that the sand must be cleaned by a process called backwashing in which water is forced backward to remove the dirt the sand has picked up.  This process uses quite a bit of water, so these filters are not recommended in dry areas where water shortage is a possibility.

The second type of swimming pool filter is the cartridge type.  These are more effective at cleaning the pool water than the sand filters and they also tend to be somewhat more expensive.  Maintenance is easy with a cartridge filter.  All you have to do is remove the cartridge and rinse it with a garden hose, then replace it.  A good filter might only need to be rinsed a few times during the summer.  Some filters are designed to be disposable and must be replaced from time to time.  Cartridge style swimming pool filters are efficient in that they require the least amount of water pressure of the three types.

The most effective type of filter is the DE swimming pool filter, as it is able to filter out tiny particles as small as five microns across.  The main downside of a DE filter is that they tend to be the most expensive.  The positive aspect is that they make the cleanest water.  Cleaning the filter is accomplished by backwash, like the sand filters, but the backwashing does not require as much water. 

If you would like to improve the filtering ability of a sand or cartridge filter, you can add some diatomaceous earth to the other types of filters.  It will lodge in the sand or cartridge and coat the inside so that smaller particles are filtered out.  Add it by putting a few cups of the powder into the swimming pool skimmer.  (DE is a widely available, safe, natural powder made up of fossilized skeletons of ancient diatoms (single celled animals) from the sea.)  Alternatively, you can add a chemical called a flocculant (or pool clarifier) to your pool water.  This chemical makes the particle matter in the pool clump up so that it makes large enough particles to be filtered out by the filter.