is greater than the outside diameter of the siphon tube 70 the lower end of the siphon cap 72 includes a leg 74 which spaces the lower end of the cap 72 above the bottom wall 66 of the liquid cup 56 an arm 76 extends upwardly from the cap 72 and then downwardly over the upper edge of the back wall 58 and into a slot 78 fig1 and 2 formed on the back wall 36 of the powder cup 48 so as to retain the siphon cap 72 in position over the siphon tube 70 the siphon tube 70 and cap 72 function in a conventional manner so as to siphon liquid detergent upwardly in the space between the cap 72 and the tube 70 and then downwardly through the tube the tube 70 discharges into the powder cup 48 wherein the liquid detergent flows by gravity out the opening 54 and then into the bottom 26 of the base 16 for drainage out the drain opening 28 it is further understood that powder detergent cup 48 can be molded integrally with dispenser base 16 while still maintaining the prewash compartment 98 the liquid detergent cup 56 would then be selectively mounted within the integral powder detergent area when it is desired to use liquid.