View Full Version : Calcium problem?

01/15/2006, 08:40 PM
I have a question in regards to my calcium levels...

My calcium is 600 according to Hagen test kits; Salifert will not even read as reagent runs out before color changes. KH is at 150 which is a little high, but corals are very healthy. (Mg levels are within normal parameters of saliferts test kit)

I have been using Reef Solution which I am told has a high concentration of Magnesium. As a result, told Mg will give a false - positive reading for Ca.. Is this correct?

I never dose any calcium to my tank of any kind, but the levels should be falling. Livestock I know should drain Ca levels in my 104gallon reef are 4 squamosa clams (all above 6"), 2 x 5" crocea, 3 x 2"-5" maxima clams, and numerous acros.

Does anyone have any clues or insight? I gladly welcome all points of view and expertise... I am thinking of maybe just taking a water sample to a lab and have it professionally tested.

01/15/2006, 09:28 PM
Alk at 150 ppm is not high at all. I would bump it to 9-10 dKh which is 160-180. If your mag. is about 1300-1400 ppm then that is fine. By chance using Oceanic salt?

01/15/2006, 09:32 PM
I'm using Reef Crystals. I will start raising my Kh. Do you think this will "align" my Ca levels? I was wondering if maybe the corals were taking up more Mg, than Ca. I have heard of this happening, making the sps more brittle.

01/15/2006, 09:39 PM
It's not far enough to throw it that far out. I'm not familiar with Reef Solutions, does it contain any calcium at all? Test a fresh mixed salt batch and see what it has. I know Reef Crystals had more than the IO but I was thinking mid 400's but thats a complete guess.

01/16/2006, 09:53 AM
You can use the Salifert test. Once you exhaust the first syringe, fill the syringe again to the 1.0 ml mark and add until color changes. Add the two values together and you get your ppm. :)

Randy Holmes-Farley
01/17/2006, 05:25 AM
As a result, told Mg will give a false - positive reading for Ca.. Is this correct?

With a quality kit, it won't. :)

I'd just maintain alkalinity with something like baking soda, and allow the calcium to decline on its own for a while. This article and calculator may be useful:

Solving Calcium and Alkalinity Problems

Reef Chemicals Calculator

steve the plumb
01/18/2006, 12:52 AM
you can test at half volume with salifert that way you get more tests out of the kit.You will be able to tell youer 600 ppm with 1 syringe vs 2.I would let the calcium depleat on its own.