Abstract: The easily serviced aeration apparatus of the invention includes a central base structure comprising a source of air under pressure, a plurality of lateral passages extending radially outward from the source, a diffuser hanger at the outward end of each lateral passage, and a dependant assembly suspended in hanging relationship downwardly from each hanger. Each dependant assembly comprises a downwardly depending flexible air conduit, an aeration diffuser at the lower end of the conduit, and means for maintaining the diffuser at a submerged depth as air is fed thereto. Additionally provided is a porous plastic aeration diffuser.