I had an ebb and flow on the top of my goldfish tank, growing lettuce for my rabbits. Then my pump died a horrible, silent death and I went back to deep water culture, which still works well for mint and lettuce.
I could never get enough plant growth to do more than mildly supplement water changes, though. It has been very frustrating. I have given up on soliciting advice.
I keep thinking that if I could plumb in a bigger hydroponics area, I would get somewhere. But I would also need lots of grow lights, and a huge pump with a prefilter that would need to be cleaned daily, and I just don't have the space or the money.
Forgot to mention that I have dreamed of an aquaponics system where the excess produce was used to grow a secondary meat source, though worm bin may be better for the system.