Richard's viv has a great piece of driftwood that is the perfect height for basking, but his claws are so flat from the tile floor that he has trouble gripping it and feeling secure. When he's on that log he slides on his belly like a snake, but on the others he trots around normally. How can I "roughen" it up to give him more confidence on it without causing splinters? Or could I wrap it in something so he'd walk on it more easily?