Are Danio's aggressive? Need help

[BigDadddy]

I started a fish in cycle with regular grey Danio fish, three of them. In the first week I observed what seems to me like an Alpha male fish. He continues to chase the other two and nip fins on occasion. I've just added a school of zebra danios, about two weeks in. This alpha male is continuing to harass the rest of the tank, especially the zebras (which are a bit smaller). Is this normal behavior for the Danio? Is there anything g I could do? I feel like it may be stressing the fish. It certainly stresses me out.

Thanks in advance

 

[blert]

They are not really aggressive but they are very active and a touch crazy. They seems to enjoy playing chase and causing a ruckus. Just make sure there are plenty of hiding places and stuff to break line-of-sight so the they can take a break if need be.

 

[librarygirl]

You could try a couple of things:
1) get a breeder net and put the aggressive fish in. This will allow other fish to see him and he them but still keep him in the tank while isolating him from harassing anyone. Then after a few days, release him back into the tank. This makes him the "new" fish rather than the dominant one.
2) Re-arrange some decorations which will throw off their territories and make them establish new ones.

If either of those don't work and he's that aggressive you might just want to rehome it.

 

[phishfriend]

Also, if this is the second week of a fish in cycle. I wouldn't add any more fish at this point. What are your levels like? I know the cycle has nothing to do with aggression.