I have one that is somewhat nervous when I first reach into his tub. He doesn't hiss or strike but he usually balls right up and buries his head. I just try not to make any sudden moves and don't touch his head. I stoke him a bit and he starts to relax. Once I pick him up he is ok. He gets better from week to week. He will get there eventually. He is eating, shedding and pooping so I'm happy.