In my opinion, no sand is safe to use for tortoises. Not the calci-sand nor the desert sand. Tortoise stomachs are similar to those of a horse, and ingested sand accumulates due to gravity in the lower portion, and can't make it up and out into the digestive tract. Keeping the tortoise very well-hydrated helps with the problem, but its a risk I won't take.
No its is not safe, and it also prevents you from providing the correct environment for your baby. Please read these ASAP. Every minute that passes in your dry enclosure is a minute closer to eventual death from dehydration. You have been given the old incorrect info about how to care for them. READ READ READ! PLEASE.
Never use sand, it can get into the tortoises body and will not come out that easily, it can also scratch the tortoises carapace (Read this from a book so might not be true) so just don't use sand. Good thing you asked.