Damsel on damsel violence

[farmerbob]

Hi,
I started a 30 gallon foWOlr tank and added two damsels almost a week ago -they're the popular purple/gold juveniles you always see in LFSs.
I had thought that being the only two fish in a 30 gallon tank would give them plenty or personal room, but one is constantly seeking out the other and uprooting "him" from his hideaway. I'm assuming they're both male by this behavior. The underdog is losing some of his fins as a result.
I was suprised by it because damsels are typically schoolers.
What do I need to do?

 

[sepulatian]

Damsels are only schooling fish in large schools (7+). Even then they have a heirarchy system, the weakest gets picked on until it dies, then the next weakest gets picked on and so on. They are likely to harass any other fish that you add. You may want to think about returning them or, if you want to keep just them, adding plenty of caves and territories. They often claim many spots as their own. They are known to pick on fish much larger than themselves.

 

[new-guy]

i had to put a divider in the tank for almost a week but they seem to chill out for a while... i put in a egg crate as the divider

 

[t316]

Originally Posted by farmerbob
Hi,
I started a 30 gallon foWOlr tank and added two damsels almost a week ago -they're the popular purple/gold juveniles you always see in LFSs.
I had thought that being the only two fish in a 30 gallon tank would give them plenty or personal room, but one is constantly seeking out the other and uprooting "him" from his hideaway. I'm assuming they're both male by this behavior. The underdog is losing some of his fins as a result.
What do I need to do?

You'd be surprised. In the fish world, it's often the female than rules the roost, and she will dominate the male to no end.