A built-in filter prevents sand or small fish from being sucked in. Keeps the aquarium clean and provides a comfortable living environment for your fish. Product features: sand washing, sand changing water, hake droppings, as long as you shake it gently, you can do it, it is not only very simple and convenient, but also environmentally friendly, most importantly, you can enjoy the fun of fish farming. Keep your fish healthy. The inlet filter is designed to prevent fish/sand from being sucked out. Strong suction and large flow rate. With the sand washing cylinder, you can easily remove the waste in the sand with water. It can be cleaned and collected in a short time, it is very time-saving, you can adjust the flow rate with the button as needed.