Pests:
You could try "no pest strips" to kill mites and other insects... All other insects!!
They are available at stores like Home Depot, and Lowes. They cost $5.00 each and work incredibly well.
I recently went through a nasty infestation of mites in one of my cages. A fellow herper gave me the following advice.
1) Clean the cage.
2) Cut a No-Pest-Strip in half.
3) Hang the No-Pest-Strip out of reach of your pet.
4) Make sure there is some air flow.
5) Leave in for 24 hrs. NO LONGER as it can cause kidney damage.
6) Remove the strip for a few days.
7) Repeat if needed.
I would not recommend this if I was not sure of how well it works. I would also recommend that you talk to others about this
if you would have your tortoise in the cage while eliminating pests. You could also place the mulch into a large cardboard box and place a few strips inside. Place the box outside in the sun for a few days. Do not let the strip contact the mulch, place it in a coffee can with some holes poked through.
I also leave a strip hanging in the room that I keep my reptiles in 24/7. It is about 20 or so feet away, and near a window. I've been doing this for about a month with no dead reptiles... just bugs!!
Bedding:
Why not use a mixture of Timothy Hay and Cypress Mulch? This works well for my little Black Tortoise. He will nibble at the hay, and there is enough air space in the bedding to allow it to dry out between misting. I also use large flat stones to add variation to the cage and help with filing the nails down.
Anyway, I hope this helps or gives you some ideas. It cost me about $25.00 for enough stones, mulch, and hay to cover a 3X5 floor, and my little dude seems to be in heaven.
PLEASE BE CAREFUL IF YOU PLACE A NO PEST STRIP IN A CAGE WITH YOUR PET. WHAT WORKED FOR ME COULD BE DISASTER FOR YOU.
-Kory