I think I understand. So you think that 6" is as high as I can go with the baffles? I knew that there would be some drain back from the lines, but I was thinking 2-3 inches would do it. I guess 6 inches is good beacuse I think they come in pre-cut sheets of 12"x12".

I will draw up a new diagram and go from there. Thanks for all your help so-far, this project has evolved quite a bit since I started!