Abstract: In accordance with embodiments of apparatus and methods, a control valve suitable for use with a gravity-assisted flush toilet is presented providing means for automatically controlling the supply of mains water to the bowl. In accordance with some embodiments, the control valve supplies at least a portion of the mains water from the fill valve bowl outlet to the tank reservoir until the tank water level is at a predetermined height in the tank reservoir, at which time, the control valve diverts at least a portion of the mains water supplied by the fill valve bowl outlet to the overflow pipe, and therefore to the bowl.