Blue-Greeb Chromis on timeout - how long?

[Crustoceous]

I have a 175g fairly well stocked, including 5 blue-green chromis. One has turned into a bully, so much that none of the other chromis will come out. He even bullies other unrelated fish, mainly the clowns. I caught him and put him on timeout in the refugium day before yesterday. Since then the other chromis have finally come out of hiding.

Has anyone dealt with this in chromis, and if so, how long do you think is an appropriate timeout? A month? Two months? Forever?



——
Edit: awesome, typo in the title and I can’t change it. I swear I’m not an idiot...

 

[landlubber]

i vote forever.
Chromis seem especially intent on asserting dominance and the fish isn't likely to value the lessons learned in the penalty box.
i actually lost one myself last night and am crossing my fingers it ends there.

 

[Baldguy]

I started with seven and ended up with one. Seems to be the normal course of events with these Chromis. There will be exceptions but sooner or later you'll be left with one. Do a search and you'll see many threads on this subject.

 

[marcolipe]

Yes sadly true , 1

 

[Uncle99]

48 hours in isolation. Then a second chance.
Then, it’s not worth it if “peace” has been achieved.

 

[Fish_Sticks]

It seems to be their natural behavior. Removing on will just put another one in charge, and they dwindle down to zero.

Nobody is really sure why they do it. My guess is it's related to nutrition, and rockwork layout, but hopefully somebody has an actual idea.

Ive tried to keep a school of 7 on three seperate occassions. All end up picking themselves off.

This thread needs a chromis wizard.

 

[Sharkbait19]

This behavior is completely normal for such fish. In fact, there are a lot of fish with such behaviors. To successfully keep chromis in a school, one would need at least 20. The same can be seen in freshwater with tiger barbs and exodon tetras. Unless it's a large enough school and tank to disperse aggression, you'll always be left with one, because they try to form a hierarchy. That's just schooling behavior for many fish. In the wild, they school by the hundreds to avoid predation. Such circumstances don't exist in a reef tank. In tanks and in tiny schools, they simply don't have the instincts to stick together peacefully.

 

[PanchoG]

Chromis always go Highlander, at the end there will be only 1.

 

[Crustoceous]

This definitely makes sense. I do wish I had known this before buying them... just another thing the LFS doesn't care to mention when buying livestock...

 

[landlubber]

This definitely makes sense. I do wish I had known this before buying them... just another thing the LFS doesn't care to mention when buying livestock...

its unfortunate but on their behalf, businesses that talk consumers out of buying from them don't generally last very long.
if the 3 I recently purchased don't last I read Pajama cardinals have a better record of tolerating each other and will be the next species I go with.

 

[Fish_Sticks]

This behavior is completely normal for such fish. In fact, there are a lot of fish with such behaviors. To successfully keep chromis in a school, one would need at least 20. The same can be seen in freshwater with tiger barbs and exodon tetras. Unless it's a large enough school and tank to disperse aggression, you'll always be left with one, because they try to form a hierarchy. That's just schooling behavior for many fish. In the wild, they school by the hundreds to avoid predation. Such circumstances don't exist in a reef tank. In tanks and in tiny schools, they simply don't have the instincts to stick together peacefully.

Tempting.

Does this behavior translate as much to beng cardinals?

 

[Sharkbait19]

Tempting.

Does this behavior translate as much to beng cardinals?

Cardinalfish are very similar, except that two will pair off and fight the rest. IMO it's either dozens or one. However, cardinals might be more likely to be lenient. As far as your chromis go, damselfish are really just all around nasty.

 

[Sharkbait19]

Here's a good way to put it:
Chromis are shoaling fish, not schooling fish. The big difference is that shoalers stick together in immensely large groups to protect themselves. Though schoolers do this as well, shoalers don't need company to survive. They don't even like company. Shoals aren't necessarily one species, either. It's just a large group of fish that want to survive. Schools also swim in a patterned manner, but shoals aren't quite as organized.

 

[Uncle99]

This definitely makes sense. I do wish I had known this before buying them... just another thing the LFS doesn't care to mention when buying livestock...

You have a 175g tank.
Chromis group should do well in that size.
I have a group of 5 in my 180 for a year now, lost two at the start, but then, the killing stopped.
It might take quite some time to wipe each other out or never.
Just let them take care of business, but not harass other members other than there own species.
Harassing others....is a time out....or a rehome.

 

[Fish_Sticks]

Now... what insane black hole would open up if you put 25 cardinals and 25 chromis together?

 

[Dan_P]

I have a 175g fairly well stocked, including 5 blue-green chromis. One has turned into a bully, so much that none of the other chromis will come out. He even bullies other unrelated fish, mainly the clowns. I caught him and put him on timeout in the refugium day before yesterday. Since then the other chromis have finally come out of hiding.

Has anyone dealt with this in chromis, and if so, how long do you think is an appropriate timeout? A month? Two months? Forever?



——
Edit: awesome, typo in the title and I can’t change it. I swear I’m not an idiot...

Tough luck. Hope it works out. I have 7 Blue Green Chromis in a 75 g tank. No other fish. All is well. I could just be lucky or they are so well fed there is no need for fighting.