Ya I don't want to kill the little guy for no reason if he is going to jump, I was just hoping since he is a rock dweller that he would be less likely to jump. When I had a six line it jumped once, luckily I was there to toss him him back in. But with the six line he was all over the place darting around the rocks, so I wasn't too surprised he jumped. So I guess I was hoping the possum is less likely than the six line to jump, and since my six line only jumped once in about a year it didn't seem to be a major problem. Btw do you guys have any pictures of yours?