Abstract: A water purification system for use with a pool or the like in which a small quantity of water can be continually withdrawn from the pool for recycling. The system involves the use of silver impregnated activated charcoal granules as a combination filter and antimicrobial agent such that the need for chlorine and other conventional chemical treatment of the pool is eliminated or vastly diminished. A small portion of the water being recycled is diverted and so treated with the silver impregnated activated charcoal such that small amounts of silver ions are released into the water such that the silver concentration in the pool is maintained at a level effective to kill essentially all bacteria present therein.