Oase BioMaster 600 Canister Filter –1250l/h for aquariums up to 600 litres External Aquarium Filter – For the Highest Demands EasyClean pre-filter module – Module can be removed separately from the rest of the filter. This reduces maintenance, increases filter efficiency, and extends the life of main filter foams. Customize the pre-filter with coarse 30 ppi, fine 45 ppi, ultra-fine 60 ppi, and activated carbon 45 ppi filter foams No mess maintenance – Integrated safety locking features on the handle, pre-filter, and check valve in the inlet/outlet connection unit, ensure no accidental spillage or messy maintenance Sealed filtration pathways – Allows for the full benefits of all four stages of filtration through this intuitive design Hel-X Biomedia – An extremely large protected settlement surface (800m²/1000 litre) that allows beneficial bacteria to grow and thrive. The material is designed to stop floating as soon as it reaches a certain level of bacteria colonization. Carbon pre-filter foams – Activated carbon absorbs unwanted substances in aquarium water. Carbon filter foams make replacement much simpler than using common granular carbon.