Fluval U1 Underwater Filter - 55 L (15 US gal)Fluval Nano Aquarium Filter is an optimal water filtration system for small aquariums up to 55 litres (15 US gal), including Fluval's EBI Nano Shrimp Habitat and Fluval's Flora Aquatic Plant Kit. Equipped with foam filter media, it provides effective and thorough mechanical and biological filtration. A fine foam pad traps small debris and a Bio Foam captures debris and houses nitrifying bacteria. The filter also provides the option of adding a carbon