The present invention includes a molten metal pump and associated components that enable gas to be released into a stream of molten metal. The gas may be released into the molten metal stream (preferably into the bottom of the stream) flowing through a passage. Such a stream may be within the pump discharge and/or within a metal-transfer conduit extending from the pump discharge. The gas is released by using a gas-transfer foot that is positioned next to and is preferably attachable to the pump base or to the metal-transfer conduit. Preferably, the conduit (and/or discharge) in which the gas is released comprises two sections: a first section having a first cross-sectional area and a second section downstream of the first section and having a second cross-sectional area, wherein the second cross sectional area is larger than the first cross-sectional area. Preferably, the gas is released into or near the second section so that the gas is released into an area of relatively lower pressure.