Abstract: A fluid mixer for submerging within a body of liquid to transfer and mix the fluid in the body of liquid. The mixer does not draw liquid through an opening and has no sharp corners so debris within the body of liquid cannot plug the mixer. The apparatus comprises a rotatable shaft with a hollow passage and a fluid intake to the hollow passage. An impeller is attached to the end of the shaft. The impeller has two circular discs, substantially the same diameter. The discs are coaxial with the shaft and have a space therebetween. The hollow passage within the shaft is in communication with the space between the discs. A plurality of impeller blades are spaced apart about the impeller and extend outwards from the space between the discs.

Abstract: A submerged aeration apparatus has a hollow shaft extending downwards from the surface of a body of liquid. The hollow shaft is used to transfer surface air or other gases to the body of liquid. An outlet for gas near the bottom end of the shaft is positioned below the surface of the body of liquid. An impeller connected to the shaft near the outlet for gas has an aperture adjacent the shaft for drawing liquid towards the impeller and circulating the liquid past the gas outlet for mixing the liquid with the gas, the impeller then expelling the liquid.