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Swimming Pool Filter 101

Keeping your swimming pool clean is the most essential part of pool ownership. The circulation of water allows the pool chemicals to keep the water sanitized and crystal clear. This is greatly aided by the type of pool filter that you use in your swimming pool. The three types of pool filters are sand, cartridge and Diatomaceous Earth. No matter the type of filter you have in your pool; your pool is just a pond without a good pool filter.

Sand Filters

Sand filters are the easiest to use of all the types of pool filters. Their operation is very basic, but excellent at doing the job of removing dirt and debris from your pool. Pool water is pumped into the filter and the sand traps the containments. The tighter the sand is packed in the filter the better. The water must work itself through the tightly compacted sand and is more likely to catch unwanted visitors. Sand filters are more efficient when they are slightly dirty; consequently they should only be backwashed when required by the increase in pressure. Sand filters should be cleaned at least every season with a filter cleaner. Dirt is removed from a sand filter by “backwashing” or reversing the water flow. Ask your pool professional about the proper “backwashing” procedure, as they change depending on the type of pool filter you have. The filter should be backwashed when the pressure gauge on the filter unit indicates a 7-10 lbs. increase over normal operating pressure. This is the pressure indicated on the pressure gauge when the filter is completely clean. A sand filter can filter the pool’s water down to about 25-30 microns of dirt. This is extremely beneficial at keeping your pool’s water clean and crystal clear. Consult your pool professional for the frequency requirements for changing the sand.

Sand Filters | Pool Filter

Diatomaceous Earth Filters

Diatomaceous Earth, or D.E., pool filters will give your pool the cleanest water of all the types of pool filters. D.E. filters out the finest particulates down to about 5 microns. The Diatomaceous Earth pool filter is actually made out of the exoskeleton of algae. Like sand filters, the D.E. filter is cleaned by backwashing the filter when pressure increases 7-10 lbs. However, once the filter has been backwashed, new Diatomaceous Earth must be added to coat the grids in the filter. This is accomplished by pouring D.E. through the skimmer. Your pool professional can tell you how much DE is required to “recharge” your filter. To cut oils and other natural oil build-up, Diatomaceous Earth filter grids should be cleaned at least once every season using filter cleaner and thoroughly as well as being inspected for tears or rips in the grids.

Diatomaceous Earth Filters | Pool Filter

Cartridge Filters

Cartridge filters have the highest capacity of all pool filter types. This filter is the hybrid of the other two types of pool filter. The cartridge pool filter only needs to be cleaned twice a year. Dirt and debris need to be removed from a cartridge filter when the pressure gauge on the filter unit indicates an increase of 7-10 lbs. over normal operation pressure. You must remove the cartridge, or cartridges, from the filter and hose off all loose dirt and debris. It is best to soak the elements in filter cleaner for at least 12 hours or as recommended. This will remove all oils and grease embedded in the cartridge. After soaking, remove the cartridge and rinse thoroughly with fresh water. Peak filter efficiency is achieved if you allow the cartridge to dry prior to reinstalling in the filter. Tip: purchase a second set of cartridge elements so they may be interchanged on a regular basis with the first set to avoid time with no pool water circulation. The filter is extremely efficient filtering the water down to 15 microns and only requires moderate maintenance for sparkling clear water.

Cartridge Filters | Pool Filter

One of the most attractive parts of a swimming pool is clean and clear pool water. It is so much more enjoyable to know that your pool has crystal clear water. The pool’s filter is the catalyst behind clear pool water. Proper filter maintenance will allow you to enjoy your backyard paradise for many years. So, when you think about enjoying your swimming pool this year, don’t forget about your pool filter.