I have a red tailed black shark. He started out in a community tank and was kind of bossy. He never actually hurt anyone, just kind of bulldozed them and then swam away. When I got tired of him being bossy in that tank, I moved him into my monster tank with green terrors and a jack dempsey. He still holds his own with them. I have also caught him sucking in baby fish so anything small with him might not be the best idea.
I also had gouramies and angels together. That didn't work out so well for the gouramies. They were all dead within two months. And that was in a 120g with lots of hiding places, plants, wood and undergravel tube tunnels. It just didn't seem to matter. I am sure some people have managed the mix well, but it didn't happen in my tank.
I have plenty of breeding BN's and I love them. In my lightly planted tanks I do find some leaves that have been munched on (Amazon swords). In a heavily planted tank, you probably wouldn't even notice it.
