These filters hang over the edge of the aquarium, leaving the body outside like a backpack. Thus, they do not take up space inside the aquarium and are ideal for small aquariums. Extremely quiet pump takes water from the aquarium and sends it to the tank . There, it goes through all the filtration stages, then comes back purified by a cascade system, oxygenating optimally. Innovative filtration technology. With their bold new look and sense of accomplishment, these one-of-a-kind filters take filtration to the next level with their high biological power, allowing all aquarium enthusiasts to keep their aquariums beautiful and healthy. /p>