Pretty much anything and everything that PPP told you was an absolute lie, including that horribly inhumane way of stopping them from biting. Gliders are not cuddly little domesticated pets. I mean they are adorable, but very much wild. Biting is something gliders due, but you can deter them from doing it by making a psst sound and promoting licking instead of biting. However, they really should be in a group of two or more. So please look into getting him a friend, and on a proper diet.