Clownfish Aggression (w/video)

overhead

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I have had these two Clownfish in a Biocube 32 for three months. They generally stay away from each other, besides the occasional aggression from the larger clownfish while feeding. Recently, I added two more fish (not clownfish) and the aggression from the larger clown toward the smaller clown has increased drastically. I am considering moving the smaller clown to a IM15 I have set up with a Tailspot Blenny. Do you think this is the right thing to do or is there something else I should try? What you see in the video is happening much of the time. Ignore the audio, as I have said before, I don't live in an Air Traffic Control tower, I just run a feed up to liveatc from the local airport and did not turn down the volume.

 
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overhead

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I would remove one of the clowns or you might wake up to a dead clown tomorrow
Thanks. Just after I posted this I watch the smaller clown smash into the glass and a rock trying to escape the larger clown. That was it for me, I checked salinaty and temperature of both tanks to ensure they were close and moved the smaller clown to the IM15. Believe it or not, now the Tailspot Blenny in the other tank is chasing the clown a little. Hopefully that will stop if the clown stays away from the Bkenny's rock/cave
 

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@overhead does the smaller clown have any ripped fins? Are they the same species of clowns? If they're the same species of clowns then it looks like normal clown behavior with the larger one turning into the female and trying to get with the younger male one.

If the fins are ripped then I would be concerned but if not looks normal to me and I've had several sets of clowns with my current pair being 15-16 years old.

You could try increasing the number of feedings (2-3 smaller meals in a day is better than once a day) as well to try and help with the aggression.
 

Jay Hemdal

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I have had these two Clownfish in a Biocube 32 for three months. They generally stay away from each other, besides the occasional aggression from the larger clownfish while feeding. Recently, I added two more fish (not clownfish) and the aggression from the larger clown toward the smaller clown has increased drastically. I am considering moving the smaller clown to a IM15 I have set up with a Tailspot Blenny. Do you think this is the right thing to do or is there something else I should try? What you see in the video is happening much of the time. Ignore the audio, as I have said before, I don't live in an Air Traffic Control tower, I just run a feed up to liveatc from the local airport and did not turn down the volume.



I call this "displaced aggression" - I've seen it a lot in Red Sea fish, but I imagine it can happen with other species. What happens is that new fish change up the dynamics of the previous group of fish and fighting starts up, even though those original fish had an "uneasy truce" for some time prior.

It *might* settle down, but it looks pretty serious to me, I'd isolate the aggressor.
 
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overhead

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@overhead does the smaller clown have any ripped fins? Are they the same species of clowns? If they're the same species of clowns then it looks like normal clown behavior with the larger one turning into the female and trying to get with the younger male one.

If the fins are ripped then I would be concerned but if not looks normal to me and I've had several sets of clowns with my current pair being 15-16 years old.

You could try increasing the number of feedings (2-3 smaller meals in a day is better than once a day) as well to try and help with the aggression.
It appeared to have a rip in a fin today, but it was hard to say. I fed two to three times a day when I was in town. Up until recently the aggression was mostly when I walked or stopped in front of the tank or when I put food in the tank. I put a camera on the tank and noticed that it was pretty much non-stop now. Again, not experienced with fish behavior at all, but I was comfortable with aggression that only went on during feeding as long as everyone was eating, but now it was constant. It did not matter where the smaller clown went, the larger clown "hunted" it down and was charging, biting, etc at it. So much so the smaller clown was frantic, smashing into the glass and rocks, etc trying to get away. It could be I am not familiar at all with fish behavior and reacted when I did not need to, I really don't know.
 
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overhead

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The smaller one seems like the similar size of the female. This isn’t normal aggressison. It’s most like they’re both female.
They were both introduced at the same time, one was slightly larger than the other when I bought them. I assumed that was the right thing to do, or, I thought it was better if one was larger than the other assuming they would figure it out. They might have figured it out on their own, but now they are in different tanks. I felt bad leaving the smaller one to be possibly killed when I had other options available
 
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overhead

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I call this "displaced aggression" - I've seen it a lot in Red Sea fish, but I imagine it can happen with other species. What happens is that new fish change up the dynamics of the previous group of fish and fighting starts up, even though those original fish had an "uneasy truce" for some time prior.

It *might* settle down, but it looks pretty serious to me, I'd isolate the aggressor.
That makes sense. The aggression went way up when I added the Royal Gramma and Watchman. To be honest the Gramma was a problem at first, just being aggressive with everything. It settled down, but the clownfish issues escalated for sure.

I moved the smaller Clown to my other tank. It seemed unethical to risk it when I had other options available.
 

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Maybe if you can re-home one. Let the other one grow out until your confident its transitioned to female. Then find the smallest most docile one in a group and add it using an acclimation box. I've found this works better than just adding two hoping they'll figure things out. Too many LFS sell two clowns and call them a pair which is far from reality IME .
 
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overhead

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Maybe if you can re-home one. Let the other one grow out until your confident its transitioned to female. Then find the smallest most docile one in a group and add it using an acclimation box. I've found this works better than just adding two hoping they'll figure things out. Too many LFS sell two clowns and call them a pair which is far from reality IME .
Fortunately, I have the Biocube 32 and an IM15. I moved the smaller clown to the IM15. It only had a Tailspot Blenny in it at the moment. The Blenny was a jerk to the Clownfish when I added it this afternoon, we will see how that goes. The LFS that sold me the Clownfish is not that normal LFS I use now, but to be fair to them they did not lie. The younger dude that I was talking to that day said "you just never know with clowns, they might be fine, they might try to merc each other" or something like that.
 
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overhead

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As long as you want to keep both in two separate tanks that's a plan.
I don't mind keeping them in different tanks. I was considering waiting 6 or 7 months and adding anemones to the IM15 anyway. I am not trying to breed fish and as long as the fish are happy without a mate that is fine with me. I once had a foster dog for 10 months that I had to keep isolated from my two resident dogs because they wanted to kill each other...this is much easier in comparison.
 
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overhead

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I'm a dog person and totally agree. My grandparents were bullmastiff breeders back in the 60s. They had 7 adults in their small home, two were intact males. I'll take clown fish aggression any day.
I have an English Bulldog/Bully mix and a rather socially inept German Shepherd. The foster was a Malinois that was two years old or so and had spent most of it's life chained up in a backyard. Things got a little spicy, as you can imagine. Mastiffs are awesome, love the breed, never had one but I have handled them a bunch in the shelter. It all ended well, was just very stressful keeping them apart. I still have a scar from the experience. It has been interesting to learn about fish behavior.
 

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