Scott's 270g aka Project Mayhem

[Myka]

Originally Posted by Scythanith

Yes but a refugium by nature is already filled with water.

Isn't your refugium filled up all the way right now? Is it next to the return chamber? Is the return chamber normally filled only partway during normal operation? If these are all "yes", then you can switch up the baffling so the refugium is part of the return chamber and is only filled partway. You should be able to get more volume then.

I can't remember what your sump looks like, and no pic on first page or this page, so I gave up looking.