【Multifunctional Aquarium Filter】: Our aquarium filter has four main functions: water pumping, oxygen supply, filtration and circulation, the aquarium pump can be used for fresh water and sea water, this filter can effectively remove pollution in the aquarium materials to create a healthier aquarium. The living environment of aquatic organisms. 【Adjustable Water Flow】: This internal aquarium filter has a maximum flow rate of up to 300L/H, which is very suitable for 40L aquarium types. It has a unique design that can adjust the water flow through the water inlet pipe on the side of the aquarium filter, thereby providing oxygen to the aquarium. 【Two Modes of Use】: The aquarium water pump has two modes of use. You can increase oxygen through the water inlet pipe and nozzle, or you can use the rainwater connecting pipe to improve the filtration effect and filter the water more thoroughly. When the water level is low, the filter can be placed on the side underwater to be used in the turtle