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Authentic
11/13/2011, 07:23 AM
I have a 30 gal nano.parameters are all good ph 8.2 ,alk 7.6 and no ammonia nitrates or nitrites. I dose with calcium carbonator at about 2 ml every three days.my tank is mostly Lps and soft corals,2 clams and three fish.I can't get. My calcium to stay over 400 any ideas?.I use a hob filter so no sump etc.

HighlandReefer
11/13/2011, 07:56 AM
Calcium carbonate which is what is in calcium carbonator from its description, will not dissolve at reef tank pH levels. The pH would need to be below 7.8 for it to start to dissolve. What happens when you add calcium carbonate fines to a reef tank is it will get skimmed out and not add much as far as alk and calcium. However the calcium carbonate will dissolve in alk and calcium test kit testing process and result in artificially high readings until it is skimmed out.

You want to use calcium chloride to maintain your calcium level. ;)

Calcium carbonate is used in calcium reactors where the CO2 added will dissolve it. :)

HighlandReefer
11/13/2011, 08:02 AM
Randy provides additional information regarding using calcium carbonate without a reactor is this article:

How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

From it:

"Calcium Carbonate without a Reactor

In a recent article22 I described in detail what one could do with calcium carbonate when not used in a reactor. In my opinion, the best use is to dissolve the calcium carbonate in fresh water, and use it as the top off water for the system. Other uses, such as adding particulate or milky products directly to the tank seem like poor practice to me (since particulate calcium carbonate likely won’t dissolve in a reef tank and may actually nucleate precipitation of additional calcium and magnesium carbonate from the water).

The big drawback to this method is that not much calcium carbonate will dissolve in fresh water, regardless of what form the material takes (including fine aragonite particles). One is limited to about 30-ppm calcium in such top off water, which is about 25 times less than is present in saturated limewater. Consequently, this system alone is only good for tanks with very low calcium and alkalinity demand, though it can be used in conjunction with just about any other supplementation system (except limewater, which uses the same top off water).

If you use products like commercial play sand for this application, the cost can be very low. A 50-pound bag of calcium carbonate sand from Home Depot costs $3.50, or less than $0.008 per thousand meq of alkalinity. If you use hobby grade products, like Aragamight, the cost is more on the order of $12 per pound, or $2.64 per thousand meq of alkalinity. Tank salinity will not increase over time using calcium carbonate.

Another use of calcium carbonate is as the substrate in a reef tank. As organic molecules are degraded inside of the substrate, the pH can drop, and the calcium carbonate can dissolve just as it does inside of a CaCO3/CO2 reactor. This rate of dissolution ends up being slow, however, and typically cannot provide a tank with adequate amounts of calcium and alkalinity unless the demand is very low.9"

Authentic
11/13/2011, 08:08 AM
Should I be using a two part calcium kit? I was recommended to use the carbonator but my lfs didn't ask what type of system I had

HighlandReefer
11/13/2011, 08:15 AM
The two-part calcium part is calcium chloride which a fine way to maintain calcium.

You can buy calcium chloride from BRS much cheaper in bulk. You can use baking soda for the alk part.

Randy provides the recipes here:

An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System
http://reefkeeping.com/issues/2006-02/rhf/index.php