Diatomaceous earth (D.E.), also called "diatomite", is a white, odorless silica powder originating from skeletons of microscopic single-cell plants. [...] Properly applied to the pressure side of filter elements, it forms a porous, relatively non-compressible coating through which water readily passes. Dirt particles, lint, hair, certain bacteria and protozoa, as well as other suspended impurities, do not pass.