I think the OP is trying to get our head worked out. The function of the refugium has been stated very clearly in the above posts, supported with nice pictures.
Yes, it's another tank. Of course you can choose to go without a ref/sump, but it will not be as good. I would think someone that has "11 yrs saltwater, 9 yrs reefing" experience would at least know about this and more willing to try to understand this instead of keep going "this is a second tank, FWIW".
|