Calcium Precipitation...

[djdubdub]

Can someone explain this process???

What does it mean exactly??? How does it happen??? How do you stop it or avoid it??? When does it happen???

Any feedback is much appreciated...

DJ...

[Charley]

From:

http://www.aquariacentral.com/articles/calcium.shtml

Calcium levels that exceed approximately 550 ppm in the typical reef setup will "precipitate" out of solution. This means that given the water conditions at the time (including elements such as pH, temperature, and alkalinity) the calcium is saturated in the water and no more can be held. At this saturation point, the calcium becomes solid and forms calcium carbonate. When this happens, the tank can appear as if it is "snowing", or may become quite cloudy. It would be logical to think that this calcium carbonate is indeed "calcium", so what's wrong with this? The problem is that this particular form of calcium is not available in a biologically acceptable form to the tank inhabitants.

[matt]

Generally speaking, most hobbyists get this "snowstorm" effect of calcium precipitation out of solution when adding too much of a 2 part calcium supplement at once, or adding both parts too close together time-wise. When adding separate calcium and carbonate supplements, you need to make sure there is some time between the additions. One friend adds calcium (part a) one day, then carbonates (part b) the next, etc.

Here's the typical scenario: you test for calcium and carbonate hardness and find you're low on both. You add some calcium chloride (like turbo calc) and then immediately some buffer (like super buffer or baking soda) and it starts snowing. If you wait an hour betwen the two, you're probably going to be fine. The precipitate is calcium carbonate as Charley said, so if you add calcium ions and carbonates at the same time, in enough quantity, they combine and there's your blizzard.

HTH
Matt