Over-aggressive female Molly

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Jaybird

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Joined
Apr 6, 2006
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I have a 30 gallon tank with a few guppies, four black mollies, and three orange sailfin mollies.

One of the female black mollies has become quite a bit aggressive as of late. She seems to just push the guppies out of her way but will nip at the other mollies and sailfins (no so much at their fins and tails but at their skin). She's boxed the male black molly and another female so much that they have become extremely stressed and just laze about on the bottom of the tank. She's even driving the larger sailfin male batty.

She seems very healthy in every other regard.
 
Black mollies usually are more aggressive compared to the others for some really strange reason, I've seen this more than once. Try removing her from the group for a while then introduce her back in a few hours later to see if maybe she'll have to get a new pecking order status. She probably just thinks that she's the big boss of the tank and she can kick anyone's butts anytime she wants X3. HTH
 
I had one (beutiful black) that behaved in exactly the same way.
A true bully.

I hated to do it,but one day I had enough and took it back to the store.The tank has been a much happier place since.

I tried to wait it out and see if it would get any better...(it was terrible at the end of feeding time)..but it only got worse.I suspect you'll find yourself in the same shape.If your going to return it the sooner the better I think.

HTH
 
There are things you can do to try to aleaveate agression..
If its relatied to territoral, rearranging the tank decor and adding more cover can work.

But, I have seen quite a few mollies that just had an adittue problem, If you happened to get one of these save yourself some stress and trade it back to the LFS.
 
I'm going to buy a separate, smaller, tank this weekend and will try transferring her there. Hopefully that will help. She is a beautiful fish (even colour, great fins, full belly)....except for the attitude problem.

With luck, this temporary relocation will help re-establish an equilibrium in the tank.
 
I had a female black molly that did the SAME thing!! She even pushed around my blue gourami!!!! She was really the pack leader. She later died though.
 
i've seen my other female mollies be aggressive toward black skirt tetras but I fixed their attitude pretty quick by taking them out for a couple days and then putting them back in and now I have a little black molly and she's at the low end of the pecking order thanks to my male Slider lol I'm breeding different colorations to see how the genetics are crossed and stuff but from what I've seen black mollies are the worst mollies out their and I have no idea why but they're usually ones to cause problems in a peaceful tank. I got that aggressive black molly at school to stop being AS aggressive by giving her a mixed school of my mollies and she's not aggressive toward them unless there's food involved
 
Feeding time is when I notice agression most with my mollies. Often times when a female is getting ready to drop fry they become agressive. What is the temp of the tank? higher temps can also have a factor in my opinion.
 
SCFatz said:
I had one (beutiful black) that behaved in exactly the same way.
A true bully.

I hated to do it,but one day I had enough and took it back to the store.The tank has been a much happier place since.

I did the exact same thing. Took my black male back and now the tank is 100% different and everyone is 10x happier. The shrimp come out all the time now too.
 
Well, the separate tank thing didn't work. I gave her a couple of days, but on her return she came back with a vengeance. I did find a solution, though. My girlfriend fell in love with a large dalmatian sailfin molly, male, and he had kind of put her in line. She's still the most aggressive female, but she's now too busy trying to feed and fend him off to bother the others. Everyone seems a bit happier now.......except for the male orange sailfin. He'll chase after the new male, occasionally, but still shows no interest in mating with the female.
 
oh jeebus. i just got 5 black mollies for my 55 gallon but i haven't seen any particular aggression yet...hopefully that won't be the case
 
SeymourFRESH said:
oh jeebus. i just got 5 black mollies for my 55 gallon but i haven't seen any particular aggression yet...hopefully that won't be the case


Not all black mollies are evil lol I notice it usually with females that've been alone and don't have a certain pecking order and most times either don't have a school or the school is a mixed bunch of mollies. I have yet to see my lone female black molly do anything yet either but she's more of a loner than follow all the other fish I have while my others always group together.
 
i have an aggressive silver balloon molly, or a sailfin-balloon molly, not sure what she is but I named her Loretta. She runs the show. When it comes to feeding she won't let any of the other mollies eat. She'll swim at them and body check them lol it's bad tho, i put her in the net to feed her seperately sometimes so every1 eats. Even when not feeding she chases my black male balloon molly (cleveland) away and body checks him. SHe does the same to my femalone non-balloon dalmation molly (sprinkle, named and chosen by my gf). Actually when sprinkle was introduced into the tank, she challenged Loretta after a day and they fought in a circle for a good 3-4 minutes until they both swam a little away and stopped. I'm going to add another female and see if she'll simmer down.
 
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