The circulation/filtration system consists of a circulating pump and filter; the pump moves the water through the system. The filter removes small particles, which if left in the water would turn the water turbid. It's important to follow the manufacturer’s instructions as to how long the circulating pump should run. Periodically the filter will require cleaning. The filter will invariably be of the cartridge type which can be cleaned with Fi-Clor Spa Cartridge Cleaner. This is essential to remove precipitated minerals and greasy deposits that have been trapped in the filter which if left, will impair the filter’s performance and cause the water to become cloudy.