Abstract: A liquid level control system for automatically stopping the flow of water in a bathtub. The system includes an adjustable level control mechanism and a flow control device. The control mechanism comprises a float suspended from a flexible chain and slidingly mounted in a vertical chamber hydraulically linked to the bathtub. When the float is buoyantly actuated by the level of the water reaching a predeterminedly set height, the flow control device obturates the inlet of water coming from the water supply conduit.