Aerator for bodies of water

In combination with a fish tank, an aerator for the fish tank comprising a centrifugal pump having a central inlet and a peripheral outlet and being of the type adapted to receive substantial quantities of air at its inlet without losing its prime, said pump comprising a casing having a rotor that rotates within said casing, said rotor having thereon a plurality of blades of airfoil configuration, conduit means having an inlet end that rests removably on the bottom of said fish tank for introducing water from the bottom of said fish tank to an elevation above the upper edge of the fish tank and into the pump inlet, means for introducing air into the pump inlet, conduit means having its outlet end disposed adjacent the bottom of the fish tank for discharging mixed air and water from the pump outlet adjacent the bottom of the fish tank, and a filter on said inlet end for introducing water into the pump inlet, said filter resting removably on the bottom of the fish tank, said filter comprising a hollow body, and a conical screen whose apex is directed inwardly of said hollow body.