He was probably too cool in the tank ... cool snakes are less active and more docile ... put a snake at it's proper temps and it's true personality comes out. Easier to keep the correct temps in a tub.

I'd just let him settle in in the tub and see how he turns out ... moving him back and forth is only going to cause more stress.

The "type" of cage can not dictate a ball pythons behavior ... security (hides) and temps can make a ball either nippy or calm.

Maybe he's hungry?

-adam