I'm looking at getting a puffer or another cool oddball for a 20 long.
If I go the puffer route, what is a good one that won't outgrow the tank?
I'm OK with brackish.
Also diet is a consideration - I think I'd like one of the ambush predator puffers more than the active hunters, because then I can keep the food in the tank (e.g. ghost shrimp, snails, etc) and hopefully make things happen in one tank instead of a separate snail growout tank.
Also open to other cool oddballs. I've considered one or more African butterfly fish (the one that hangs on top of the water, not the cichlid), since both my previous attempts with them haven't worked with tankmates. But they can be finicky to feed (either needing live foods like crickets or live feeder fish, which I'd prefer to avoid).
Open to other options as well.
Thoughts, everyone?