Aggressive Female Black Mollies

I have two black molly ladies whom are nipping/chasing my betta females. My tank is suspiciously peaceful and I'm always prepared for it to go south, so I wanted to add dither fish to break up territory.
I chose mollies as I know they are 'robust' fish that will stick up for themselves as I was concerned my girls would be rough with them. However, to my surprise the total opposite has happened.
The girls are very gentle with them but when they attempt to share food, the mollies (one in particular) will nip at their eye/head area.
I thought the mollies behaviour would dissipate when they had their fry but it has not.
I have never owned mollies before, so would increasing their number to 4-5 decrease aggression or atleast make it more towards eachother? or is this behaviour fairly normal for mollies and I should remove them?

 

I don't personally have Mollies, but I have read a number of posts about this specific topic. Female black mollies in particular commonly like to be the 'boss' of the tank. Not really the best fit for a tank with female (or any) bettas.

 

I have had Mollies before, females too, and I have never quite understood why they get called out as great peaceful community fish. My experience has been similar to what you're talking about. They will beat up on each other and some of the other tank inhabitants. I've had Angelfish that are not anywhere near as nippy and aggressive as most of the Mollies that I've had. Though I LOVE the look of Mollies, I don't know that I'll ever keep them again because I just have not had consistent luck with them being as peaceful as people say they are.

 

Unfortunately I'm dealing with aggression currently. They do have a pecking order and can be pretty nasty to one another. They also do much better in a larger tank.

 

Unfortunately I'm dealing with aggression currently. They do have a pecking order and can be pretty nasty to one another. They also do much better in a larger tank.

Yeah, you are quite right. I have sinced moved them from the 33 gallon to the 60 gallon and they have had a personality change. The extra space and the fact they aren't the biggest fish in the tank any more made a huge difference. I added 2 more for their comfort but the black mollies are more bossier than the other two which are speckled brown/black/white. They no longer bother other species of fish though.

 

Yeah, you are quite right. I have sinced moved them from the 33 gallon to the 60 gallon and they have had a personality change. The extra space and the fact they aren't the biggest fish in the tank any more made a huge difference. I added 2 more for their comfort but the black mollies are more bossier than the other two which are speckled brown/black/white. They no longer bother other species of fish though.

I'm glad you've seen a positive change!