Tom's Aquatics Stellar Air Pump Air Pump For Aquariums Sized 10 To 20 Gallons Maintains High Oxygen Levels While Providing Water Movement To Keep Fish Healthy Long lasting diaphragms plus silicone flappers for many years of trouble-free use Single Air Port Outlet; 0.76 Liter-Per-Minute Air Volume; 2.13 Psi Air Pressure Rating Full Range Of Tom Air Pumps Available For All Aquarium Sizes