Can Calcium Carbonate be used....

[tanzy]

Calcium Carbonate is not Kalk! Kalk is Calcium Hydroxide. Calcium Carbonate is near insoluble in pure water. The higher the pH the less it will dissolve. If you must use Carbonate, then you could try dissolving excess of it in hydrochloric acid but the carbonate will fizz out as carbon dioxide, leaving the Calcium ion. I don't like the idea of using inorganic acids in the aquarium. Kalk seems a lot more convenient.

 

[6_line]

Thanks,
I though because it wasn't hydroxide I wouldn't be able to do anything with it..but heck, anything for free in this hobby is worth questioning. Calcium carbonate I believe is the end result of calcification and I knew something wasn't going to work with this stuff.
I didn't even attempt to use it.
That's why there are message boards...

 

[randy holmes-farley]

Some people use finely divided calcium carbonate as a Ca++ and alkalinity supplement by dissolving it in water, and adding that water (without any solids!) to the tank. In effect, you are adding calcium ion and carbonate ion.

In most situations, it is a poor second choice to limewater, because of the much lower amounts of Ca++ and alkalinity supplied per unit of added water, but can be useful.

 

[jdeets]

Actually, if you want to use Calcium Carbonate, get a calcium reactor. That's what we use for media. The reason we use CO2 on the reactors is to lower the pH to make the compound soluble in water.

 

[randy holmes-farley]

James:

Yes, one can use a CaCO3 reactor. Using CaCO3 without any reactor is less expensive, and if you have a low need for Ca++ and alk, and don't want to use limewater, it is a useful alternative. Hence the commercial product aragamight. For example, a tank with mostly soft corals might be able to use this less expensive approach.

 

[6_line]

as a kalkwasser of some sort? Where I work there are huge bags of the stuff (it's food grade, ground limestone) and I was curious if it can be dosed as Kalk because that is what coral skeletons are formed of.

Thanks.