Patent ID: 8657122

Claim:
A media retainer assembly for retaining filter media in a gravity filter assembly, the media retainer assembly comprising: a top plate for supporting the filter media, the top plate having a top surface, a bottom surface and a plurality of openings extending therethrough; a bottom plate having a top surface and a plurality of openings extending therethrough; and scouring media, the scouring media being adapted to abrade the surfaces of the top and bottom plates, wherein the top plate is connected to the bottom plate such that the top surface of the bottom plate is spaced from the bottom surface of the top plate to define at least one chamber between the top plate and the bottom plate, the top surface of the top plate is in fluid communication with the chamber via the openings in the top plate, and the scouring media is supported by the bottom plate within the at least one chamber, wherein the media retainer assembly is adapted to be connected to an underdrain block of the gravity filter assembly such that the chamber is in fluid communication with the underdrain block via the openings in the bottom plate, wherein the top plate, the bottom plate, or both comprise a plurality of separable pieces, and wherein adjacent separable pieces of the top plate, the bottom plate, or both are connected by at least one tongue disposed on one piece fitted within at least one groove formed in an adjacent piece.