Hey P.Hippy. Glad your here. Not many people here are into critizing. How to get the most help here is simple. Just ask. If it is the sump that slopes down on the bottom from the water inlet side to the water out let side I think I know the one your talking about. Anyway the biobale/bioball chamber is quite similar to one I had to redo. I removed the topcover, the top grate, the biomedia, the bottom grate. I just put enough live rock in the tank to filter the tank. 150 lbs of valu and tonga branch. Its on a 150. I put in a skimmer, bought a extra couple of sponges (so customer can cycle them out and wash in the washing machine), put a turbo twist skimmer on it, and let it flow to the return pump area. Its not the best sump, because it was supposed to be a wet dry, but it works for a place to keep, skimmer, heater, uv steri, and return pump. If you really want to put live rock down there too. It needs to be submerged or it will work just like a bioball or biobale. Just my experince and opinion. I hope it helps you. Steve