Eliminates the need for separate recirculating and fill pumps. Keeps plumbing and electrical parts to a minimum while providing truly automatic features. Ideal for low profile bass boat configurations. Effortless cable operation.Auto-Off-Plane:Wiith boat off plane, fresh water will be constantly blended with recirculted livewell water.Auto-On-Plane:When boat is placed on plane, the control valve will automatically close the transom port to prevent water loss and the aerator pump is automatically diverted to closed recirculation duty. When off plane, the control valve automatically opens the transom port to again allow fresh oxygenated water to be added to the livewell.