I got a hamster awhile back (3 weeks or so) and he has a metal bar cage, and he keeps chewing on it. I am frightened he might chew it to were it is rusty and he gets sick. How can I get him to stop, without getting a new cage? I've tried just about everything. He also, at night, climbs up onto the ceiling of it and chews on the metal bars. And all day he sleeps in his wheel, only to come out when I am asleep. I wanted to be able to hold him like previous hamsters I've had, but he spends all his time in his wheel, which is a part of his cage. Please help