Adding Calcium to 12 gallon

[DavinD]

I recently purchased this product to help maintain calcium levels.

http://www.drsfostersmith.com/Product/Prod_Display.cfm?pcatid=4687&N=2004+113458

The directions say to add one cap full for every 20 gallons. Since I have a 12 gallon I added about half a cap full. Almost immediately all my corals closed up. Is this normal? They opened the next day as usual.

[Chris13]

I've never used this specific product but it seems strange that corals would close up. Never had mine do that when adding supplements.

I use two part alk/calc on my 24g directly to the overflow return stream. I add it at a rate of what I would call a 'slow drizzle' and watch my PH meter. I never let my PH rise more than .2 in any 4hr period.

did the water turn milky or the additive 'bead up' in the water?

[DavinD]

My corals never close up like that during the lighted period unless a snail or something crawls over them, then they pop right back out. When I add the calcium, the water clouds up for a few sconds and then it is clear.

Even my Hairy mushrooms closed up which they rarely do at all.

They were all fine when the light came back on today.

Maybe I should add the calcium to my top-off water and then add that to my tank?