Dymax Power Head (submerged motor-driven pumps) are superior pumps with respect to energy. They are the basic components for all Dymax filter systems and are also used as circulation pumps. Dymax power head pumps are continuously tested for their ecological effects under realistic conditions. They do not produce any harmful shearing forces. Dymax Power head is suitable for water feature and aquarium use and both freshwater and marine systems. Magnetic rotor technology. Adjustable flow rate. High head power. PH400: Flow rate 400L/H 5W. Suits aquarium size: 25-60Litres.