Calcium - which is best?

[nwestwood]

I've rummaged through my old hydroponic supplies, giant pumpkin supplies and garden supplies and have found 3 different types of Calcium.

I have:

Calcium Chloride 10% (liquid)

-----------------------
Biomin Calcium (liquid)
2% Organic Nitrogen
5% Chelated Calcium (Calcium Carbonat and Citric Acid)

----------------------
Calcium Nitrate (granular)
1% Ammonical Nitrate
14.5% Nitrate Nitrogen
19% Calcium (All from Ammonium calcium Nitrate Double Salt)

My system always has high P.H. 7.6+ and I have to add Phosporic Acid to bring it down.

So to supliment Calcium in my system, which of these is best? I've been using calcium chloride but I'm now out and don't know whether to get more or use up some of these others.

[Ravnis]

Not sure which is best , but I know whats cheap. Pickling lime is food grade calcium hydroxide. I mix it with vinegar and declorinated water. I add enough vinegar to get the ph to ~7.0 so it is neutral when I add it. I found this on a reefkeeping site and it helps the plants.


Make sure you let it stand for a day or so before adding it to your fish tank. It can really raise your ph high if you don't get enough vinegar or other acid to bring the ph down.