The JUWEL Bioflow Super is the perfect internal filter for entry-level aquariums of up to 150 litres in volume, providing you with a great many advantages. The Bioflow Super works on the principle that "The water should stay in the aquarium!" and is the safest way of filtering the water in your aquarium. The Bioflow Super works without hose connections which can cause leakage, also reducing pump output due to friction.