The ?Nano? model series has been designed for use in reef biotopes up to 200 litres (52 US gal.), and is gentle to plankton in operation. The DOC Skimmer 9002 removes up to 80 per cent of organic waste matter, such as protein and cellulose, from the aquarium water. Very little space is required in the aquarium, and installation and maintenance is very easy. On account of their construction, this model is particularly quiet during operation. On account of the high demands in stone coral aquariums, this skimmer should be used only in aquariums with about 100 litres (26 US gal.) of water. Mixed aquariums or soft coral aquariums up to 200 litres (52 USgal.) can be set up without any problems.