Tips for cleaning a pool filter cartridge include rinsing away debris from the pleats, soaking the filter in detergent to remove oils and soaking it in muratic acid to remove stubborn algae growth. Rinse the filter after soaks, and rinse before reinstalling it.
Once the pressure gauge reads 8 to 12 pounds per square inch above the starting pressure for the pool, it is time to clean the filter. Removal of the cover and filter depends on the manufacturer's design, so consult the owner's manual for specific directions. Use trisodium phosphate, a pool filter cleaning detergent or liquid dish soap for soaking the filter up to 10 hours to remove oily deposits.