Abstract: An apparatus for controllably dispersing material into a fluid stream with the apparatus having a housing with a bottom section that attaches to a pipe line and a top section having a cylindrical sleeve with a porous container therein to support a solid fluid soluble material. The porous container can be controllably inserted into a fluid stream through coaction of a spring and cap to control the amount of soluble material entering the fluid stream. A sealing surface on the porous container and the cylindrical sleeve prevents fluid from escaping from the line when the porous container is in the up position and an upper seal prevents leakage past the cap when the valve is in operation.