Danio behavior

Yet more fish topics! I've found that aggressive danios make a huge difference in the schooling behavior and the overall peace in the tank. Not surprising. I had to return the super aggressive danio to the fish store as it had a cut in its side which was growing ich. I'd noticed the cut originally but thought it might recuperate. Well, once I saw the ich, that guy wasn't going to stay! And so I got a replacement danio which is smaller and less aggressive than the original one. As a result, the crazy bullying has decreased, though they're still aggressive. I'll take what I can get. I wish I never got them though. =\ A new alpha danio has taken over, but definitely not as crazy as the old one. Phew!