So I don't have crushed coral as a substrate I have 120 lbs of aragonite sugar sand, but I have read that you can use it to help maintain calcium levels in a tank. I guess I should also state that I am a naturalist to a certain extent and don't believe the use in chemicals unless I absolutely have to.. So if I were to use a small bag of CC to help boost/maintain calcium levels, where should I put it, and how much should I use?