By filtration we mean the retention and removal of suspended solids from water using granular media. There exist many different natural media for this purpose. The following are the most prominent of our product range:


The most common filter media, silica sand should be pure, hard and of a uniform spherical granular size. Our Aqua Sand range fulfils all of these criteria. Aqua Sand is always from a fluvial source as crushed sand produces unwanted angular grains and dust.


Aqua Cite is a hard, uniform, low-density granular anthracite usually employed in a filter layer above Aqua Sand. This dual-layer filter bed can substantially prolong filter cycles between backwashes leading to large savings in downtime, energy and backwash water. Aqua Cite chemically fulfils the EN:12909 requirements having >90% fixed carbon, <7% ash and <10% volatile matter.


Garnet is a high-density natural alumina silicate rich in iron. This is installed in fine layers (100-200mm) below the Aqua Sand bed and is used to ‘polish’ the passing water. That is, it retains many of the very fine particles that have managed to pass through the silica layer.


The apertures in the filter floor can often get blocked by fine filter media and therefore need to be protected by support gravel. This coarse gravel forms a barrier between the filter media and the outlets without risking blockage.