I have a 75 gal with a 30 gal sump. It has 3 chambers with a refugium in middle. My question is I can fill my sump about 2-3 inches from top with out it flooding my basement. When its above my refeguI'm chamber baffle the water in the refug at top just sits there and kind of gets a thin film forming. If I take out about 7 gallons I get it just above the baffel so it overflows into my bubble trap. So what would be better having the extra 8 gallons of water with a potential film forming or -8 gallons and not having max water volume. I do have a small air pump I could put in refug to break up the surface if needed. What should I do?