Afternoon folks -

Im looking for some advise on how to combat aggressive/dominant behavior when adding new fish to an established tank.

I recently came across a beautiful spotbreasted angelfish that I wanted to add to my tank. I brought her home, acclimated and quarantined her for the past two weeks. I need to tear down my q-system so I can start the plumbing for my 180 build, so after letting her sit in the "breeders box" in my 70gal for a few hours, I let her loose in the tank.

Instantly my orange spotted tang decided she was an intruder and bullied her into a corner, and has kept her there since yesterday. Constant flaring and tail swipe/slashing at her... Im worried about my investment now.

Any thoughts on how to curb this aggressive behavior? I know the tank is a bit small for the adult specimen (only 70 gal), but they are young and small (angels ~2.5", tang ~2") and their new home is in the works now. Id prefer to not rip apart the display to pull one out if I dont have to, and im going to eventually add more fish to any tank from here on out.

hmmm... current tank residents:

2 lyretail anthias
1 occelaris clown
1 twinspot hogfish
Orangespotted tang
Spotbreasted angel
1 red firefish (I see him like once every month)
1 blue-green chromis

Everybody but the angel has been in the tank over a year.


I apologize about the washed out blue - I barely had the lights on so I could take her picture in the tank, but still dark so it would abate the aggression.
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