so i have my long 180 up and running it feels pretty empty as of right now has a 1ft bichir and fire eel a variegated shark pleco 2 BGK 2 clown loach and 3 angels. besides the angels almost everything just relaxes in the wood and live plants and mostly hangs around the bottom. im trying to think of a good mid/upper tank schooling fish to add. I was considering balas but would love some other interesting ideas?