The tasks of the different layers in a filter

Aside from the physical contaminants that are trapped by the filter material (mechanical filtration), water also contains toxic chemical elements. These are generated by the decay of organic waste (fish excrement, plant residue, excess food) and are invisible since they are dissolved in the water. Bacteria transforms this organic waste to ammonia (NH₃) or ammonium (NH₄) and then to nitrite (NO₂) and at the end to nitrate (NO₃) (biological filtration).

The mechanical filtration is done in the different layers of filter materials of different densities. Coarse contaminants are trapped by the first coarse filter materials. The following layers, with finer materials, will trap the finer contaminants that cause physical cloudiness.

Important function of the filter material, for the biological filtration, is the ability to host the greatest possible number of microorganisms to clean the aquarium water of its organic waste. Aquarium Münster products for the mechanical and biological filtration are characterized by their high level of quality. The use of AQUAVITAL filter media ensures that the different layers in a filter are matched to each other in a perfect way.