Ideas about what's wrong with the tank?

Before y'all start to rip this post apart, it's about to be cleaned and the tank as well. But it sounds like this still after a full deep clean of both the tank and the all parts of the filter. The top later let's you remove the top piece into two and I've gotten in there and scrubbed it down, cleared the pipes as best I can, make sure there's no air in the tubing by pumping the button too. I'm thinking I just need to get a better system for more money