I am trying to load pictures on here as requested but not having luck. If someone can help me figure out how to do that I will certainly be happy to attach those. The overflow is drilled on the back wall of the tank a few inches from the top and a bulkhead is on that hole. I then have a pvc elbow screwed into the bulkhead inside the tank. On top of the elbow is a cone shaped filter type thing.

On the back of the tank I had another elbow screwed into the bulkhead and the clear tubing was run directly to the sump underneath. It sounded like a waterfall and was very loud unless the tubing was draining directly into the sump and not allowing the water to fall into the sump. When I put it directly into the sump there was no air getting into the tube, though, so it sounded like a toilet flushing whenever it needed the air in for flow.

So I was told to try putting a pvc tee on the back of the tank. This allowed me to submerse the end of the tubing, which cuts out a lot of noise, but now it sounds like it is draining nonstop instead. While this is not as loud as before, it is still quite noisy. Any ideas on what to do from here?

Thank you.