Uhh, let's see...
Imagine your tank as a jar of jelly beans. Each day your corals pull one white(calcium) and one blue(alkalinity) jelly bean from the the jar. Eventually the jar starts to empty and you have to refill it. If you add only white jelly beans, the jar will become imbalanced. Something else happens too. Those white jelly beans you added kick a few blue jelly beans out of the jar, so you become even further imbalanced.
Magnesium is your mom. The more magnesium available the harder it is for jelly beans to fly out of the jar themselves and elope, but that also means it is harder for corals to pull jelly beans out of the jar. High magnesium means your mom is paying closer attention to the jar, low magnesium means she's on the phone with her sister and you can sneak your hand in the jar and get a few jelly beans.
From what I've read, it to get them in balance you have to dose more of each in equal parts. My issue is I don't have much alkalinity consumption right now and I don't want to go over 9.0dKH. I've done a pretty good job of stripping phosphates from my water with GFO in my reactor, and high alkalinity with low phosphates tends to burn corals, especially SPS.
I'm going to see what dosing the extra calcium carbonate did tomorrow, then wait until my alk is down to 8.0dKH and start dosing equal parts to keep alk at that level. Calcium should balance itself out in time.
I eventually want to switch to the ATI Essentials 3 part, which is a complete foundation and trace elements 3 part suppliment that is designed to be dosed in a 1:1:1 ratio at an alkalinity of 8.0dKH.
