Pools on the CLEAR COMFORT system maintain superior clarity due to CLEAR COMFORT'S ability to take out dirt, oils and solids from the water and deposit them on the filter. Therefore, it is CRITICAL that CLEAR COMFORT filters be chemically cleaned when opening and closing the pool, and every 6 weeks during the swimming season. Clogged filters can seriously reduce water flow through the filter resulting in hazy or cloudy water. CLEAR COMFORT FILTER CLEANER is the only filter cleaner specially formulated to remove dirt, oils, dead algae and other filter clogging deposits from sand, D.E., and cartridge filters from biguanide treated pools. Its use also helps extend the life of your filter's media. 1 Quart