Zebra danio aggression
I recently added 8 zebra danios to a 20 gallon planted tank (no tank mates for now). Anyways, I've never had this fish so I'm not very familiar with their behavior, but I've noticed a lot of aggression. It's constant chasing, and I noticed today that one of them has a nipped fin. Any idea as to why this might be?
pH 8, Ammonia/nitrite 0, nitrate super low, temp 74 F