Calcium bicarbonate exists in solution but not as a solid. (If you dry out the solution, you get calcium carbonate.). So you can’t add that.
You want to target a minimum value of calcium (50 ppm, or more, depending on who you ask), but too much calcium isn’t really ever an issue. You could add too much calcium chloride or calcium sulfate, but it would be too much because of the chloride or sulfate, not the calcium. Calcium pretty much has no sensory footprint and it only does good things for the various chemical reactions that go on in the mash.
Edit: Enh,
maybe not. But I'll stand by my statement that
generally you're not going to have to worry about too much calcium.
Sodium has a taste (salty) but you usually don’t have enough to notice it, or (in the case of dark beers where you add it on purpose) the effect on taste is positive.
Magnesium, on the other hand, can cause harsh and unpleasant tastes as you get above 10-20 ppm, and cause GI problems if you get way above it.