I don’t know how big your eel was, or maybe you just got incredibly lucky. I have an almost 3 ft long snowflake and if he gets hungry he will definitely eat fish, I’ve never seen him actually catch a fish but I know 100% he’s the one eating them, I’ve seen him try. I’d say if you can manage to keep him well fed you’ll be good. But eels are choosy, they eat when they want to eat. If I attempted to feed my eel everyday I’d probably have less casualties but I would waste a lot more food trying to feed him on days he doesn’t want to eat.
I’m thinking the same thing though, make a Predator tank for him but I’ve seen my tangs “F my eel up” and I’m scared to put a humu humu in with him. What if the trigger attacked my eel? The eel really can’t defend himself against the tangs so I doubt he could hurt a trigger if he needed to.