This wasn't an intentional reduction, it's just has been dropping radically. No control. Rich thinks it's been due to the Purple Up carp.
Crap it is. There is no magic coraline solution. Except one thing, Alk and CA in perfect balance. You need to come check out my frag tank. I can't see thru it lol.
The other thing I was thinking, a long shot. You finally got everything in balance and have seen a sudden uptake in calcium (alk follows). But you don't have alot of stony corals yet. Hrmmm....
This is a new tank. Like I said, the natural, mostly hands off approach works well for me. Obviously this is an ecosystem in a box, and needs work. But less hands on, from our brief conversation you are excited, and want things to be perfect. Think of this as an F-16 (as far as I know from numerous sims), perfection comes from experience and practice. Patience. As the tank matures, it will find a delicate balance. From that balance you can perfect YOUR ideal parameters, and find the best formula for growth in your situation.
In my limited experience trying to perfect your alk/ca down to the tenths is a recipe for disaster. Every tank is unique, as unique as the reef you are trying to replicate. You have to remember every reef is different, PH/alk/CA etc.. You have a mixed reef, so your mileage may vary.
And above else, remember, what works for one, doesn't work for all. Your system is as individual as we are as people. Sit back, enjoy the tank as it goes thru numerous beautiful, and very annoying changes/cycles. :p