I know for sure that it hooks up to the outlet tube and it doen't hook up to the air pump. On the back of the package it hows a picture of it but just a hose hooked up to the back and the air line hose that has a black valve on it to control air flow Maybe you could for more bubbles but I was looking for more on placement. There is a a powerful jet flow coming out of it. I have discus and they don't like fast moving water the main reason that I bought this filter. Maybe I just won't use it if the discus would not perfer it. Any opinons?