The best way to tell when a pool filter is ready to be cleaned is by checking its pressure gauge. This is located at the top of the filter and will display the current water pressure (in psi). The filter needs to be clean when the reading on the gauge starts to rise more than 8 psi above the starting pressure of the cartridge.
This increase in pressure is caused by dirt and debris collected on the filter that clogs some of the spaces between the filter fibers. This clogging reduces the ability of the filter to effectively trap and hold debris, so it’s important to clean it often enough to avoid this build up.
A pool filter is an expensive piece of equipment, so you want to make sure it is well maintained. One of the best ways to do this is by cleaning the filter regularly with a cleaning solution specifically made for that purpose. This can be purchased at any local pool store.
To clean a pool filter, first drain it by releasing the air valve found at the top of the filter tank. Remove the collar that holds the filter cover in place, then lift the cartridge straight up and set it down somewhere to be cleaned away from the pool. Once the cartridge has been removed, rinse it off with a hose to wash off any major particles. Next, use a brush designed for cleaning cartridge filters to get into the cracks and crevices. Finally, soak the filter for up to an hour in a cleaning solution, then rinse it off again.
When a pool filter is clean, it should be brushed down again to get rid of any remaining bits of debris, then reassembled and returned to its container. It’s also a good time to inspect the filter for any signs of damage. If you notice any cracks or tears, then you should consider replacing it with a new one.
There is no hard and fast rule on how often you should clean a pool filter, but you’ll probably need to do it once every two to six weeks, depending on how heavily the pool is used. It’s also a good idea to clean your pool filter every time you change the pool sanitizer concentration or chemical levels, as this will help prevent the dirty water from re-entering the pool.
Some people also like to use a device called an air compressor to blow off any remaining debris from the cartridge. This can help to reduce the amount of water needed to clean the filter, and it is particularly useful when a lot of oily build-up from sunscreen and bather wastes has built up on the cartridge material. Others will use a degreaser such as a generic filter cleaner or a pool degreaser to deep clean their cartridges. Once the filter is fully clean, it can be reinserted into its container and the air valve turned back to a closed position.