Venturi Injector is also called water jet. It is composed of nozzle, suction chamber and diffuser. It is a kind of multi-purpose aeration method developed by using the principle of negative pressure of jet. The unique design of mixing chamber, the strong mixing of water and air, makes the mixing uniform and complete, and produces many and delicate bubbles. The oxygen conversion rate of traditional aeration equipment is generally less than 10%, and the oxygen conversion rate of jet aeration equipment can reach more than 25%.