Increasing Calcium

[BobbyC]

My corralline is not taking off like I had hoped, so I had the calcium levels tested and found it to be at 100. My understanding is that it needs to be at 400-450.

Whats the best way to approach increasing the Ca? I found a lot of different adds on the web; from Kent I'm looking at Liquid Calcium, Turbo Calcium (Dry form) or Kalkwasser. Are there major differences in each of these? Also, am I jeopardizing other water parameters by messing with the Ca? Everything else tests great.

by the way, I have a 55g FOw/LR; several snails, hermits, CBS and sand sifter with two clowns and a coral beauty.

I appreciate any input available.

thanks
BobbyC

[mogurnda]

I have a hard time believing that your Ca is really at 100. How much do you trust your test kit?

In any case, calcium is one of the components that often needs to be replenished. Corals, snails and some macroalgae consume it. If there's a small demand, water changes may do the trick, but many (most?) marine aquarists need to add it.

Dosing calcium is relatively simple, but it has to be balanced by the addition of carbonate for it to be useful. There are several methods, such as kalkwasser, two-part additives, and various reactors, depending on your budget. Two part additives, like ESV B-Ionic, allow you to adjust calcium and alkalinity (ie carbonate) independently. Kalk is cheap, but you are adding calcium hydroxide in fixed amounts. It also needs to be dosed slowly to prevent pH swings.

Randy Holmes-Farley wrote a really good article (http://www.advancedaquarist.com/issues/nov2002/chem.htm) for Advanced Aquarist, describing the range of Ca and alkalinity you want to be in, and how to get there.
Much better than anything I can write here.

[BobbyC]

Thanks Dave,
I don't have much confidence in the test, the clerk at the LFS didn't seem to know what she was doing. I'll likely get a test kit, especially if I adjust the levels.
I read the article and its informative but I guess I have one more question: If I'm going to buy a supplement to increase calcium should I go ahead and buy the two-part system that ensures the balance? If I only buy the calcium now isn't it likely I'll need to adjust the alkalinity in the future?

If I'm missing something here let me know.

Thanks
Bobby