I don't know what to think at this point. Did my LFS just need to make a sale, thus telling me i needed a Kalkwasser? I mean i spent like $100.00 on this, and we all know in todays economy, moneys really scarce. I'm just ready to give up on the corals, and just have a FOWLR. I can't afford to keep throwing money away. I'm really bummed. I'm thinking tomorrow i'm gonna change out like 40 gallons of water, and see how that works. As i said, it's a 210 gallon, with a 40 gallon refugium. Think about 40 gallons is a good amount?