The Slim S15 Power Filter's unique design is compact and slim, thus reducing space behind your aquarium. The filter comes equipped with an adjustable flow control so you can control the water flow level in your tank. Its motor is submerged in the tank for a quiet operation and an easy start-up since no priming is required. Just plug in and go! Installation and maintenance are quick, easy and convenient and the Slim S15 Power Filter includes 3 filter cartridges: 2 Bio-Carb and 1 Bio-Clear. Both cartridges contain Ceramitek, which is engineered to optimize biological filtration, for a healthy aquarium.