Abstract: The present invention is directed to rigid filtration apparatus comprising a filter support and filter membrane. Such filter support is comprised of a central core. Radiating from the central core are a plurality of pleats composed of two angled walls terminating at a contact point. Such longitudinal walls circumscribe a longitudinal channel situated between the walls wherein the longitudinal channel is in communication with the central core. The longitudinal walls are comprised of a plurality of openings along the walls. A filter membrane having biocidal components may be utilized with the filter support to effectively treat contaminated fluid, gas or air. Alternatively, the composition of the rigid central core and the rigid pleats may be composed of different materials to selectively remove chemicals, biological components or pharmaceuticals in a multi-stage treatment process.