I have 6 rummynose, they all shoal very tightly together from one side of the tank to the other, very funny to watch. They keep themselves to themselves, i have never seen any sort of fin nipping or aggression. They are quite pale in the morning until the lights come on, then they have really vivid red heads. They are quite sensitive to nitrates. They can get grey burn marks on their sides. I'm hoping to get a few more! love them