Bioscape Tropic Air Pump Double Outlet Series 3000 Bioscape Air Pumps are designed to increase water movement in aquariums for proper oxygenation. Available in 6 sizes these high quality air pumps operate quietly and efficiently. Ranging from single, dual and quad outlets there is a size suitable for all aquariums types up to 600L. The two largest sizes have an adjustable air flow. Energy efficient motor Ultra quiet operation Powerful and reliable For fresh and marine Bonus check valve's for each outlet Specifications Double Outlet with 2 Check Valves 2x 180 litres of air per hour Suitable for < 100-300Litres tanks Directions: Attach Aquarium air hose (sold separately) to air pump at desired length. Attach the air hose to the chosen product for the aquarium; air stones, sponges filters and air driven ornaments are some examples. (sold separately) Place the product into the aquarium ensuring that the pump remains in a dry place. Using an Air Pump without a check valve The Air Pump needs to be placed higher than the aquarium to prevent water siphoning in the event of a power failure. Using an Air Pump with a check valve The Air Pump can be place lower than the aquarium, like in the cabinet. The check valve will prevent water siphoning in the event of a power outage.