From what i hear Calci-Sand is bad news for a number of reasons.

I would use something like newspaper of Reptile Carpet that is simple. Newspaper is either super cheap or free in most cases and Reptile Carpet can be thrown in the wash with some bleach and used again and again

I use Reptile Carpet and i think its the best !!

I used to use newspaper but Reptile Carpet looks so much nicer.