Why Are My Male Mollies Suddenly Fighting ?

[BellasTank]

I currently have 8 mollies in my 40 gallon along with other peaceful community fish, last night one of my female mollies had babies and I managed to find 6 this morning which I moved into a breeder net on the side of my tank, the 3 males I have were the first 3 fish I got for my 40 gallon, I didn't know how to tell the gender till I looked it up after I got home and realised they were all males, I heard it was best not to have just males together so I got 3 females and then 2 more, I've had the mollies for about a month and have never seen them really fight ( I'd never even seen them flare their fins until today ) but today all 3 males are fighting pretty aggressively, two of them just had a pretty brutal fight and where continuously biting each other, I'd really appreciate any suggestions on why this has started happening and how I can help stop them ? The only idea I could come up with as to why they've just started fighting now is that there is now a molly who isn't pregnant as she just had babies so maybe they're fighting over her but yea that's just the only idea I have, thankyou very much for any help I really want happy fish

 

[NavigatorBlack]

They are triggered by hormones in the water. The recent birth means the females can be refertilized, and mollies have a social structure with an alpha - especially sailfin mollies. The alpha wants the other males to leave his territory, and if they don't, he sees it as a direct challenge to his status. He doesn't understand the glass walls. In the wild, your other two males would run so far you'd never see them again, but they are trapped now.
He may calm down and back off, but once they get started, they can also kill each other.

 

[TexasDomer]

I'd rehome all of your females. An all-male molly tank should be fine (with no females to compete over) and this way you won't be overrun with fry - females can continue to reproduce for up to a year after mating with a male.

 

[BellasTank]

That's disappointing one of the mollies had fry previously with them all in the tank but I only managed to find one and I didn't have a breeder net or anything so he got eaten but there were no problems then so it's strange it's only just started, I'd prefer not to have to rehome them all cus I really like my mollies but I will if I have to I could possibly try and just rehome my big male Dalmatian molly as he's the main one who causes issues, they've calmed down with the fighting today but the Dalmatian just seems to be standing his ground as he still flares his fin but he's not attacking the others anymore, and I don't mind that they have fry regularly cus I love the little babies and if I didn't want more they'll just eat them if I don't move them, I have a 5 gallon almost cycled and ready for a betta but if the fighting gets too bad I'll have to move the Dalmatian molly into there till I find him a new home :/ is there anything I could do that would calm them down a bit ? thankyou very very much for the help

 

[TexasDomer]

I'd still rehome the females to help your males get along (and to control fry - really, some can survive and then you'll have to rehome them as well).