Abstract: A drum filter is provided including a rotatably mounted, generally cylindrical drum with a filter and vacuum drainage associated therewith. The deck structure comprises a plurality of circumferentially spaced, axially extending, and radially projecting imperforate members affixed at one end to the outer peripheral surface of the drum and having an outer end on which said filter is supported. The members each include a pair of circumferentially spaced, axially extending, and radially projecting imperforate surfaces. Perforate members are preferably formed in a substantially "U" shaped cross-sectional configuration comprising a pair of sidewall members connected to a floor member, which in turn is joined to and supported on the outer peripheral surface of the filter drum. The opposed surfaces of the members together define filtrate slots which form open axially extending channels adapted to receive at least a substantial portion of the filtrate after the drum rotates past the twelve o'clock position.