I have a new 20 gallon long with refugium. The baffles are removeable, so the refugium does not have any sand or mud in it. Just some chaeto. It goes: pump into first chamber with multi sl skimmer in the same chamber. The skimmer pushes the water back into this chamber as well. This overflows into the refugium with the chaeto and live rock. That water flows under a low baffle, then it goes over a 4 inch one to the return pump. In between the two baffles is some carbon and a media filter. What do you guys think I can do to improve anything?