A sanitizing system for sanitizing a water flow at a point of use, the sanitizing system including an ozone demand indicator configured for determining the existence of a demand for ozone in the water flow; an ozone generator configured to be disposed no more than about 72 inches upstream of the point of use on a fluid conductor supplying the water flow at the point of use, wherein ozone generated by the ozone generator is configured to be disposed in the water flow to sanitize the water flow; and a controller operable to control the ozone demand indicator and the ozone generator responsive to the ozone demand indicator, wherein the controller is configured to cause the ozone generator to start generating ozone upon receiving an indication from the ozone demand indicator that the demand for ozone exists.