Hi Charlotte,
Welcome to The Tortoise Table. Just to check -- when you sa you were told that 'this isn't suitable material for a humid hide', were you talking about the moss (I assume it is sphagnum moss) or the wooden box? I think a wooden box could present problems because if it is very damp over a period of time it could get a bit mouldy, but I'm not actually sure. If this is the case then you could try a plastic hide -- something like this is cheap (although they do come in rather lurid colours):
https://www.amazon.co.uk/Living-World-D ... B001B5EE3C or if you google plastic rabbit or guinea pig hides more interesting one will come up.
Humid hides are very popular, but you would need to make sure that it doesn't get too cold in the hide, because although tortoises do well in warm and damp, they don't like cold and damp. A drop in temperature at night is natural for a tortoise, but try and avoid cold and damp.
Personally I achieve a bit of humidity by having other areas of the table damp. For example, I have decorative grasses and spider plants that I grow in the substrate (it's a topsoil/playsand substrate), and they are watered regularly and so produce some humidity. I've attached some photos of my table that I took tonight. I emptied all of the old substrate out today, in preparation for my tortoises coming out of hibernation this week, so it looks a bit bare as I have only just planted it up and there is more to come, and there is no water in the water bowl (and of course no tortoises in it), but you can see how planting around the table could produce humidity. I also have a ramp leading up to a second level in my table (you can see it in one photo), and that is always nice to put in a table because they get lots of exercise walking up and down the ramp.
Nina
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