and into chamber 20 where the water contacts the halogen 21 which is in bulk form and is shown located below the water line 20 a in the chamber 20 in this example a rotatable control valve 17 allows one to increase or decrease the amount of water flowing into chamber 20 and consequently into contact with the bulk chlorine tablets 21 by reducing or increasing the spacing between valve end 17 a and passage 16 once the water contacts the halogen tablets 21 the water can flow out of chamber 20 through a fluid passage 23 a in a vertical stand tube 23 and back into the venturi 13 through the port 24 a cover 27 which is sealed to the housing 11 through an annular seal 28 normally maintains the bulk feeder in a closed condition when the system is in use it is this type of feeder that is prone to over halogenation because the water flows freely through the halogen tablets 21 before being discharged through the stand tube 23 fig2 shows another typical example of a prior art bulk halogen feeder 30 which is sold by rainbow lifeguard products inc having a cylindrical housing 31 with a lower main.