My advice to you if your sump is going below your tank, is to do a smaller sump. You’ll need the real estate for other stuff. I used to have a 75 gallon sump under my tank and it took up way too much room. Plus, I just don’t see the benefit of having a big sump? With my 40 breeder, I have room to isolate all of my electronics and have a huge ATO resivoir. Even still, I’m nearly about of room in my cabinet.do mind if I ask where did you get your baffles? I am going to have to build my sump since I can't find anyone to purchase one from. I purchased a 210-gallon tank and I am looking for a 75 - 100-gallon sump. I guess I can make it which I don't mind.