Patent ID: 7507334

Claim:
In a water treatment system having only one carbon/remineralization filter connected to a filter inlet line receiving RO-treated water from an RO treatment unit, a filter outlet line connected to the downstream side of the filter, and a water storage tank, the improvement comprising: 1) a recirculation line in fluid communication with the filter outlet line and the filter inlet line; 2) a first check valve in the recirculation line oriented to permit water to flow from the filter outlet line towards the storage tank; and 3) a second check valve in the recirculation line oriented to permit water to flow from the storage tank towards the filter inlet line, wherein the storage tank is in fluid communication with the recirculation line at a point between the first and second check valves such that in use, water from the RO treatment unit must flow through the filter once before entering the storage tank, and water from the storage tank must flow through the same filter again in order to exit the water treatment system.