Fluval U2 Underwater Filter - 110 L (30 US Gal)Fluval U2 Underwater Filter provides complete and efficient 3 stage filtration, including BioMax biological filtering, to create superior aquarium water quality. The U2 Filter includes practical and versatile features, making it ideal for application in fresh, marine and reptile environments. The filter provides the option of setting the flow output in 3 different positions, a key benchmark in underwater filtration. The adjustable 3 way flow control