Hydro-anthracite is a filtration material made by the sorting of milled anthracite . Characterised by low bulk density, rough surface and sharp edges, hydro-anthracite is used for filtering drinking, pool and industrial water for mechanical impurities. Hydro-anthracite has applications in drinking water treatment, swimming pool filtration and in two- or multi-layer filters, where it increases filtration capacity and backflush efficiency. It is a very good option for the pre-treatment of liquids prior to their entering downstream equipment. Hydro-anthracite is well suited for combination with quartz sand, where it forms the first filtration layer.