Install a two tank PFOS reduction system with a total of 2 cubic feet of 110 reduction resin distributed equally in to mineral tanks. Passive in/out Clack valves with by-pass valves are included. Re-bed existing carbon system. Take a new tank, bed and media. The tanks are installed in sequence and we advise annual water testing for the inclusion. When the results become elevated the resin must be replaced. The replacement interval is dependent on the amount of contaminant being removed and the amount of water that flows through the system.