Rendezvous Spa Natural Clear (Enzyme) PINT Rendezvous Natural Clear Enzyme Clarifier for Spa or Hot Tubs - 16oz Keeps Spa Water Crystal Clear Protects Filters from Oily Build-Up and Clogging Compatible with Chlorine, Bromine, Biguanide, Ozone and Mineral Purification Systems 1 fl oz per 500 gallons of spa or hot tub water