Is adding calcium safe?

[altoids]

is adding calcium for my snails safe for my crystal red shrimp?

[TitoC]

In a recent post - http://www.shrimpnow.com/forum/show...hlight=calcium - someone is saying that a certain crs breeder even adds it to induce molting/mating.

As crs do not do well in hard water with high pH, I would not recommend adding too much. And avoid too sudden changes.