Abstract: A portable device is provided for generating a current in a vessel having a side-wall, the vessel containing a fluid. The device includes a housing having an inlet and an outlet, and a motor attached to the housing. A propeller, driven by the motor, is positioned in the housing. A float is attached to the housing to create a buoyant force sufficient to keep the portable device afloat in the fluid. Fluid is drawn into the housing through the inlet side and forced out of the housing through the outlet side to generate the current in the vessel.