Too much corals ... to little calcium !!!

[Zurk]

I added a few corals ... well, too much corals at once.
The calcium, that was in 400 / 450 dropped to 200.
What can I do to reestablish it in a short time ?
I didn't want to add kalkwasser.
Thanks

Zurk

[Randy Holmes-Farley]

I don't know how that would happen unless you have supplemented alkalinity. Corals cannot use that much calcium without a lot of alkalinity being supplied to them. So be careful that it is not a testing error.

That said, calcium chloride is the way to raise the calcium level back up. This article details the correction with calcium chloride:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm