Alright, I think I'll try feeding him in his enclosure next week! Our house isn't very busy during the day, but do you think putting a sheet over the top of the enclosure may make him feel a bit more secure? That way, there's no chance of our other pets bothering him while he's trying to eat.
When I feed him outside of his enclosure I keep him in my bedroom with the door shut and the tub covered to make him feel more secure, but I suppose even just moving him from one tank to another could be freaking him out.