I have seen the "wiskers" or barbells become a problem. From my experience they do not grow back like the fins do. I have a friend with 3 big aros and 2 are missing "wiskers" they look like stubs.
As far as feeding at that size I would try small crickets, just watch that he is eating them and don't leave them in the tank too long if he doesn't eat them. I found that as a baby my aro liked the way a cricket moved across the water and he loves them as a snack now!
I have seen the "wiskers" or barbells become a problem. From my experience they do not grow back like the fins do. I have a friend with 3 big aros and 2 are missing "wiskers" they look like stubs.