Actually people may think that adults wont die on calci sand but sooner or later they will ive had it happen to me myself i had a Albino one a while back full grown ready to breed and everything, then she died so i looked at the stomach and you could the see the black blotches where the sand was sitting in her stomach and i tried to avoid it more by not even feeding her in the cage and she still got impacted. So to me its more of those better safe then sorry situations.
And yes, i meant UVB thank you for correcting me.