Fluval UVC In-Line ClarifierQuickly and easily connected to most canister filter setups, the UVC In Line Clarifier eliminates suspended bacteria and algae for a clear and healthy aquarium. A chemical free and maintenance free way to purify water Eradicates suspended bacteria and algae in the water column that contribute to cloudy and green water, respectively Helps prevent the growth of cyanobacteria that often smothers and destroys aquatic plants Does not harm beneficial,