Dominent Danio

[weezebegs]

Yesterday I purchsed 2 zebra Danios's to go with my 2 golden Danio's.

The larger of the original danio's will not.....and I mean not... leave the newbies alone.
For the last 30 hours he has been chasing them around relentlessly and is pecking at their tail fin. I have looked closely and have not seen any nips on their fins so I don't think he is actually biting them but I am just worried that he may be stressing them out.

Is this common when adding new fish to a tank or do I need to seperate them....

 

[Caprichoso]

Hi,
You could separate them or try adding more(if you can). Sometimes fish mellow out if they are in a bigger school. Even so called "community fish" can have aggression issues. If you can't add more because of tank size then I might take them out. It's been my experience that even if an aggressive fish can't inflict damage directly, it can still chase it incessantly and cause the weaker fish to dash themselves on the glass or hide. Either one will most likely spell death in end.
Good luck!

 

[Gvilleguy]

They usually settle out the pecking order, but I agree it can wear the new fish out. A couple more might help like the prior user said.