What are my chromis doing?

[Acro maniac]

Zack,
They'll be down to 1 in a few months

Not sure why you say they'll be down to one. I've had 3 since 2009 and the ingaged in this behavior and none of them have ever shown signs of distress at the least.
Fwiw the post above i siad they are ingaging in warfare was a sarcastic remark.

 

[Acro maniac]

Thank you guys for the advice. Is there any way to lessen this aggression? Adding another chromis during lights out?

I haven't actually seen them full on attack each other though

I have never seen ripped or torn fins on any of mine. I think this more like chest bumping they will find there place in the pecking order. If you see signs of fins showing stress i would think about taking steps to correct the situation.
Ive had to remove a couple fish for aggression before. Most recent was aflame angel witnessed biting fins on other tankmate. Also a couple years ago i had a 6line wrasse that was beating up my mandrine, gone also.

 

[eatbreakfast]

The locking of jaws is full on fighting for dominance, definitely more aggressive than chest bumping. But the reason they do it is, not to fight to the death, but to establish rank in the hierarchy and therefore get the better territory and choice of mates. However, in small tanks, it may lead to death if there is not enough space, even though that is not the purpose.

I would not recommend adding a single individual to these two though.

 

[Empress]

Thank you guys for the advice. Is there any way to lessen this aggression? Adding another chromis during lights out?

I haven't actually seen them full on attack each other though

How long have they all been together in the same tank?

 

[Tristan]

What size tank? I've had quite a bit of success keeping groups long-term i mms tanks 4' or longer. Larger groups(8+), frequent feedings a day, high flow in the top of the tank.

A small group of just a few individuals, smaller tank, and only one to two feedings a day lead to increased aggression.

It's a 25 gallon

 

[Acro maniac]

25 gal IMO is a little tight for chromis. These guys are very active i have mine in a 90 and the way they move around the tank, i couldn't image keeping them in anything less the 48in length. Im sure there are others with more fish knowledge then me that will chime in.

 

[4FordFamily]

25 gal IMO is a little tight for chromis. These guys are very active i have mine in a 90 and the way they move around the tank, i couldn't image keeping them in anything less the 48in length. Im sure there are others with more fish knowledge then me that will chime in.

X2

 

[wattson]

some chromis species are to be in the Damsel family,,thats where the attitude comes from

 

[MikeYasin]

I have never seen ripped or torn fins on any of mine. I think this more like chest bumping they will find there place in the pecking order. If you see signs of fins showing stress i would think about taking steps to correct the situation.
Ive had to remove a couple fish for aggression before. Most recent was aflame angel witnessed biting fins on other tankmate. Also a couple years ago i had a 6line wrasse that was beating up my mandrine, gone also.

6 line wrasses are little punks. Mine had to go to a new home as well.