Abstract: An apparatus for utilizing gray water for flushing a toilet is provided including a holding tank with a top face, a bottom face, and a periphery formed therebetween thus defining an interior space. The holding tank has an inlet pipe connected to a source of gray water for receiving gray water therefrom. An outlet pipe is connected between the holding tank adjacent to the bottom face thereof and a toilet. A tee is situated on the outlet pipe between the holding tank and the toilet. The tee has an opening coupled to a water supply adapted to supply water of a first pressure. The tee further has a valve having a first orientation for allowing the flow of water only from the water supply to the toilet and a second orientation for allowing the flow of water only from the holding tank to the toilet. A pump is coupled to the outlet pipe between the holding tank and the compression tee.