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If their group is out of ratio (too many males not enough females to chase around) or there are only a couple, they, in my experience are bad behaved in a peaceful community.
I started with 6 and now have 3 baby cherry barbs, so 9 all together. I have them with long fin leopard danios and have not had any nipping. They are a nice calm and hardy little fish. They are much happier in small groups. I don't know your tank size, but generally they are kept in groups of 6 or more.
Opinions and individual experiences will vary. Individual schools will vary. I kept 12 with only three males and they were aggressive enough to as a group stand off gouramis. I had the same experience with tiger barbs. This was in a standard 55. I ended up removing all tiger or cherry barbs and going with tetras. I understand lots of people have success with them but between me and a few of my local (*ahem, older) fish keeping buddies we've always had issues with nipping anything with flowy fins.