These fully submersable filters are quiet trouble free and are safe to use in fresh or salt water. Can be used in Aquariums, Ponds, Terrariums, Fountains, or any place where filtration and water movement is needed. Adjustable flow rates and air injection units come with each unit. Internal foam sponge is excellent for Mechanical and Biological filtration. Optional spray bar distributes water evenly over the surface. This unit is excellent for aquariums up to 10 gallons. Filters 70 GPH.