Please don't.Sooooo I've tried the Eco Earth and I now have one fed up tortoise - he hates it!
I've pressed it down firmly but it keeps coming loose and getting into his water bowl and his food. He really doesn't seem to be happy with the new substrate so I'm going to change back to the pellet substrate he was on before.
Temperamental tortoise lol
The substrate does come loose. It dies get dug up and it does get dragged into the water bowl.
You will not keep it tidy. Torts like it that way. You cannot be OCD with a picture perfect enclosure if you own a tortoise.
The substrate does need to be damp - tip water in and mix it with your hands - and then helps to keep it under control.
As an alternative try coco coir or orchid bark. Both can be bought from garden centres. They should be kept damp too.