Josh - I normally try to keep it around 3.0 - 3.5. Lately I've been struggling to get it back up from 1.5. A large dose of kalkwasser got dumped into my sump and it drove the alk way down. Beleive it when someone tells you alk has a lot to do with growing coraline. I've lost just about all mine. It is starting to come back slowly.
I keep mine at 12 dkh all the time and here's a little info on my tank. It is 6 feet long and I use 2x400 MH and 2x250 MH lights with 2x96 pc. On the 250 watts side the coralline is really growing whereas the 400 watts side there is hardly any coralline at all. Now go figure. Due to higher energy bill in Ca. I will just run 2 tanks and one FOWLR and and SPS tank.
Toptank, to keep it at 12 dkh I'm using an MTC pro-cal calcium reactor. It has been running this way now for almost two years. Now the big question is do I check my calcium level? I did at first but the calcium level was always way above 500 and so I called the mtc people and I was advised that I should not worry about it and just work on my DKH level.Levels of 8 to 10 is fine but I want mine a little higher. So now I just check my dkh level once a month and not worry too much about the calcium level. I know that a lot of people might disagree with their concept but it worked for me. Never tested my calcium level in a long time, just my DKH level. I haven't notice any snowing in my tank either. HTH. I'm in the process of consolidating my tanks because of the high energy cost here in CA.
