1.The biochemical sponge filter provides effective filtration and increases the oxygen level to ensure a clean tank environment. It features fine cleaning effect, quietness and easy maintenance. Fit for shrimp, fry and various ornamental fish like betta, guppy, and goldfish. 2.Fine Sponge Filtration: The biochemical sponge filter provides mechanical and bio filtration and traps debris or waste without sucking up your fish, keeping a crystal-clear water tank. 3.Easy to set up & clean: simply install an airline into the unit and turn on the air pump, simply rinse and squeeze sponge in tank water. 4. Quiet environment: This air-driven biochemical sponge filter creates a gentle flow without causing disturbance to you or your fish. 5.Safe for fish: soft sponge material, traps floating debris and won't suck up your fish.