Permeable Synthetic Collectors (PSCs) are bodies of some millimetres consisting of a highly porous arrangement of fixed fibres or open-porous plastic foam. The advantages of the application of this media in deep bed filtration were studied. The theoretical analysis of the particle transport efficiency was based on the numerical solution of the flow field and on trajectory calculations for non-Brownian particles. Investigations with an endoscope allowed the consideration of the particle adhesion on the surface of the inner fibres. The resulting filter coefficients are compared with experimental data. The application of PSC filtration in a pilot scale unit for wastewater treatment performs much better in contrast to conventional filter grains (sand, anthracite etc.), especially under high rate conditions. In the future, the deep filtration can be applied to new fields of the topic of solid liquid separation with smaller units, lower pressure drop and higher filtration rates.