Abstract: This invention relates to a float controlled dispenser for automatically releasing predetermined amounts of a detergent or a bacteriostatic liquid into the flush tank of a toilet bowl whenever the bowl is flushed. The dispenser comprises a bottle necked container mounted in an inverted position in the flush tank and a dispensing valve assembly consisting of a plug having a tapered end and force fitted into the neck portion of the bottle, said plug having a central orifice circumscribed by an annular planar valve seat and of a bell shaped float member having an annular measuring chamber in which is centrally located a vertical fluted stem projection for limiting the float's up and down movement within the plug's central orifice. The base of the stem projection is circumscribed by an annular planar surface for sealing contact with the plug's planar annular surface.