The Hydor FLO rotating water deflector rotates 360 degrees driven by the water flow of the filter being used, so no additional power source is required. The FLO rotating water flow creates a natural and pleasant wave effect which is beneficial to live plants and reef inhabitants and leads to increased oxygenation. Adaptors are included which allow the FLO rotating water deflector to be used with most aquarium filter and water pump applications. For freshwater or marine aquariums. Ideal for use with canister filters and powerheads. For use with devices with flow rates of 80-310 gph. Excessive flow rates can damage the unit and are not covered by warranty.