Abstract: A contactor media for removing waste from water comprising at least two mated discs. Each disc having parallel raised ribs separated by parallel inverted ribs in an alternating rib-inverted rib pattern. Every rib and inverted rib has a series of uniformly spaced apart recesses with the recesses of the ribs located on the side of the disc opposite the recesses of the inverted ribs. The mated discs have the recesses of the inverted ribs of one disc interfitted with the recesses of the ribs of the other disc, and the two mated discs form crossing chordal channels for the flow of waste water therein and the deposit of waste on the surfaces thereof.