Water treatment

A method of maintaining spa water suitable for human immersion during a period of at least two months without having to shock the spa water to remove chloramines comprising the steps of:

• adding chlorine and 1,3-Dichloro-5,5-dimethylhydantoin to the spa water;
• placing a source of silver ions in the spa water to lower a sanitizing concentration of chlorine to between 0.25 and 1.5 ppm;
• and
• subjecting the spa water to bather use while maintaining the sanitizing concentration of chlorine.

A method of extending a use life of a body of recreational water while reducing a concentration of chlorine required to effectively sanitize the body of recreational water comprising the steps of:

• adding a sanitizing concentration of total available chlorine to the body of recreation water that is suitable for human partial immersion in the body of recreation water;
• adding a source of silver ions and a source of 1,3-Dichloro-5,5-dimethylhydantoin to the body of recreational water to lower the concentration of chlorine required to effectively sanitize the body of recreational water;
• and
• maintaining a concentration of silver ions and a concentration of the source of 1,3-Dichloro-5,5-dimethylhydantoin effective at extending the use life of the body of recreational by at least 2 folds before a required chlorine shocking of the recreational body of water.