Ozone Combo 57 Watt UV units are ideal for water features. Using the same germicidal rays as the sun, but hundreds of times stronger UV offers a reliable, cost effective, environmentally friendly alternative to chemicals and their resulting bi-products. Ozone is highly effective in removing color, organics and pesticides. It is an economical natural and non-polluting method. Water flows through the unit body and is treated by the UV’s germicidal rays. The Ozone is then injected by the consumer’s venturi into the water line adding residual effectiveness.