Our new Ultra Violet filter is easy and quick to use. It filters and cleans your pond in three ways: 1.Mechanical and Biological Filtration pads clean debris from the pond and are a perfect home for beneficial bacteria 2. Our 5 watt UV Sterilizer, built into the floating filter, reduces micro-organisms and bacteria resulting in clean, clear water 3.The fountain head helps add oxygen back into the pond with the clean water accelerating aerobic activity which leads to clean water. This technically advanced UV light uses cold cathode bulb and emits 254 nanometers-which is the optimum wavelength for sterilization. Simple. Just drop it in and plug it in and you are on your way to a clean, healthy pond.