Fighting Ocellaris Clowns

[FreshCoastReef]

So two weeks back I added a pair of designer ocellaris clownfish to my 20 g. They did great the first four days, one was doing the "male dance" and showing signs of submission. Then suddenly on day 5 they started fighting viciously.

Fighting, grappling, biting, even locking onto fins, tails, and gill plates and shaking. I've kept many fish before and this behavior really seems like more than just establishing pecking order - it seems like aggression with intent to harm.

So I put one in a breeder box for a full week. In the same tank and visible to the other clown, but separated. I was hopeful they would have resolve their differences. Yesterday I spent some time observing their behavior, and after seeing no visible signs of aggression I attempted a reintroduction. Unfortunately within 5 minutes they were right back at it.

I have now placed the opposite clown in the breeder box.

This is a bummer because I'd really like to have a compatible pair, but keeping these two specific individuals together seems like it could be a recipe for disaster.

So I'm curious, if you've dealt with this problem before, how did you resolve it?

 

[bruno3047]

So two weeks back I added a pair of designer ocellaris clownfish to my 20 g. They did great the first four days, one was doing the "male dance" and showing signs of submission. Then suddenly on day 5 they started fighting viciously.

Fighting, grappling, biting, even locking onto fins, tails, and gill plates and shaking. I've kept many fish before and this behavior really seems like more than just establishing pecking order - it seems like aggression with intent to harm.

So I put one in a breeder box for a full week. In the same tank and visible to the other clown, but separated. I was hopeful they would have resolve their differences. Yesterday I spent some time observing their behavior, and after seeing no visible signs of aggression I attempted a reintroduction. Unfortunately within 5 minutes they were right back at it.

I have now placed the opposite clown in the breeder box.

This is a bummer because I'd really like to have a compatible pair, but keeping these two specific individuals together seems like it could be a recipe for disaster.

So I'm curious, if you've dealt with this problem before, how did you resolve it?

I had the exact same issue with my Ocellaris clown fish. The attacks were brutal. But when I removed one from the tank, the other one looked lost. And then when I put him back, they were swimming together for a few days and then they started fighting again. I think it’s just a mating ritual to decide who’s going to be the female. They’re love taps. Too funny. BTW. Mine have now been together since May 2019. I removed them from the DT and I’m now trying to get them to breed in a separate tank, just them in the tank alone.

 

[FreshCoastReef]

Thanks @bruno3047 how long did you observe the fighting behavior for?

 

[bruno3047]

Thanks @bruno3047 how long did you observe the fighting behavior for?

There was always one of them that was more belligerent. It would run at the other one like a battering ram, but never made contact. If you’ve ever seen a clown kill another fish, they use their bodies like a battering ram until the other fish is just turned into a dead piece of meat. So this was always in evidence. However, for about a one, maybe one and a half months, maybe about six months ago, the more docile one became very angry and started fighting back. I even witnessed a torn tailfin, which was unusual because they never damaged each other before. What I noticed was that the more aggressive fish was trying to corner the other fish into a spot where he could prepare it for her to lay her eggs. This was about 2-3 months ago. I recently added some small fish, and they tried to kill all of them so I removed the clowns from the DT and put them into their own tank to see if I can get them to breed in there. In the new tank, they always swim side-by-side. It’s obvious now they’re in love. I don’t know what that other stuff was all about. Probably about who was going to be the female. I’ve read that they can become very violent when that transition is taking place. Good luck.