A built-in filter prevents the suction of sand or small fish. Keeps the aquarium clean gives your fish a pleasant living environment. Product features: Sand washing, changing water, hake droppings, as long as you shake gently, you can do it, it is not only very simple and convenient, but also environmentally friendly, especially you can enjoy the fun of fish farming . Keep your fish healthy.Inlet filter is to prevent fish/sand is sucked out. Strong suction and large flow. The sand washing cylinder allows you to take the waste in the sand with water easily. it can clean and collect in a short time, it’s very time-saving, you can adjust the flow rate with knob as request.