I'm building a sump/refugium from a 30 gal tank, its 36" long by 15" high. I'm trying figure the height of the various baffles. My first 2 baffles will be over/ under, followed b a 4" baffle coming off the bottom (for bubble control). That will make the intake chamber. Next the refugium, followed by 3 more baffles to form the return chamber Those 3 baffles will be over/ under and then another 4 " baffle coming up from the bottom. So I need to know how tall each baffle should be. I'm planning to set the baffles which allow water to flow under them to be 1.5" off the bottom. I hope this makes sense.