Is he aggressively biting and snapping at everything that moves or is he just coiled up? Is he biting the rodents and letting go (aggression) or biting and then eating? I can't tell from what you wrote if he is really aggressive or if he just has a good feeding response. If he is snapping and biting rodents and then letting go, a true aggressive posture, I'd say it's your glass tank and hide. I had several snakes in setups like that and they really got mean. I switched to an ARS tub, grey tubs, not transparent, and they almost overnight became puppy dog tame. He probably feels exposed in that setup. He may be OK if it's feeding response instead of true aggression, really depends on the snake and how comfortable they feel, but I'm guessing if it's aggression it's your glass tank.
Feeding in a separate tank is an old wives tale, don't do it. You have to pull them out of feeding mode to move them, then move a snake that just ate, risking regurgitation. It's the craziest thing I've ever heard of.