No - no need to add any supplements just for live rock.
If you add corals, particularly calcifying corals, they'll deplete calcium and carbonate, and you'll probably need to supplement.
That's putting the cart before the horse, though. Calcium and Carbonate Hardness (Alkalinity) are a couple of water parameters that you should be aware of. There are a few others - salinity, pH, temperature, ammonia, nitrite, nitrate. Magnesium and Posphate are good to know, too. There are some great articles in the Reef Chemistry forum that discuss them.
You should know each parameter before you supplement it - where it is, what your target is, and which dosage will achieve the target - testing afterward to verify. "Don't supplement what you don't test for" ('not sure who to credit for that!).