Aggression in the tank


New Member
Ok I seem to have a bit of ... tension in the tank. I have a school of 3 firefish and a pair of ocellarus clown fish. The firefish where in the tank first and chose their home. Waited a week or so and added in the clowns and they took the firefish spot. Actually the clowns seem to own the whole tank (90 gallons). I am in the process of moving the clowns into my refugium (my old 55 gallon) to see if the firefish behavior improves.

Has anyone experienced their firefish losing their dorsal fins? They hide all the time and only two of them come out at a time when feeding. Then they head back in their new rock.

Other than that I guess I will want some suggestions to replace the clowns. I am in the process of upgrading lighting to accomodate corals and clams. So no longer a FOWLR. Current inhabitants are

3 Firefish
2 Ocellarus (in fuge until I can determine who is beating up this one firefish)
1 cleaner shrimp
1 peppermint shrimp
1 pom pom crab
6 astrea snails
4 cerith snails
about 8 or so Nassarius snails
dwarf blue leg hermits
dwarf zebra hermits
1 white hermit (very personable)

Lighting is more than likely going to be the 2 x 250 MH (14,000k) with 2 x 54watt T5 actinic.

Suggestions please.


New Member
I at one time had a clown fish and a firefish in the same tank, and they got along fine. Perhaps the fact that the fish all want the same spot is an indicator that there is simply not enough real estate for the two groups? I would try reorganizing the rock/reef to supply more caves/recesses prior to replacing fish. I would make sure to eliminate the current hot spot. I also would add the clowns immediately post landscape change so the fish claim different areas (hopefully). If that doesnt work, perhaps some bangaii cardinals? Ive never had an issue with them...

Another solution is my clowns have always loved hammer corals. Perhaps try adding a hammer/anchor coral for them to hide in.


New Member
Thanks! Seems the firefish we the culprits. LOL I had three that seemed to be ok with each other, but two paired up and the third was beating BOTH of them up. The aggressor has been relocated and the tank is doing well.