I always supplemented mine the same way I did the chameleons and left a little lid of calcium in the cage so they could lick it up if they wanted to. Mine were just the normal color though. I don't know if morphs would have different needs or not. I also used a UVB long linear tube light over their cages. They both lived to be over 19 (I stopped counting at 19).
BtW, I did use sand as a substrate....but it was washed playsand. Never use that calcisand...it will impact them. The sand I used was the one produced by Kings that comes in a white bag with red, blue, yellow sand box toys on the front.