EHEIM Liberty 200 Hang On Filter for up to 50 US Gallons Easy installation by simply hanging over the tank edge Comes complete with filter media, therefore immediately ready for operation New large filter sponge for high biological filter efficiency and longer life Phenol-free cellular foam cartridge for reliable removal of solved pollutants With a cellular foam cartridge (accessory, order no. 2615270) in the intake area ideal for nursery tanks