A transfer apparatus for facilitating transfer between a higher density fluid and a lower density fluid. The apparatus includes a transfer chamber includes a higher density fluid zone and a lower density fluid zone adjacent each other. A moveable contactor is housed in the transfer chamber. At least a portion of the moveable contactor is moveable between the higher density fluid zone and the lower density fluid zone. A current generator connected to the transfer chamber generates a current in the lower density fluid zone. A transfer system includes a plurality of fluidly connected apparatuses in series.