Please help! Molly Fish Aggression

[Lauren4events]

Can someone please help? My dalmatian molly fish had fry. I wasn't planning on keeping them… But I fell in love. I purchased a 60 gallon tank which has all 12 of the molly fry. No other fish.5 males, 7 females. They are about 3 months old now. The problem I'm having, is for the past few days all of the males have been chasing one female. They don't seem to be bothering any other females in the tank. She seems incredibly stressed and always trying to get away from them. Her breathing is also heavy. I'm worried she's going to die. They will not give her a break? Is there anything I can do to stop the aggression towards her or to get them to leave her alone? I'm not sure why they are leaving the other females alone and all chasing her at once. It's 5 fish harassing 1 and I feel horrible for her. I'm assuming this is sexual. But I'm not sure why they aren't interested in the other females? I really don't want to get rid of any fish, but I can't purchase another tank. I have 3 now (which is another story entirely but too much work as it is).
I'm not sure if this is related, but I just noticed a couple new fry in this tank. I didn't know they were even old enough to have babies of their own. It's getting out of hand! I've only found a couple. The rest of them were probably eaten. Or hiding well.
Any help here would be really appreciated. Thank you!

 

[evil wizard]

Do you have another tank where you could move the harassed female to? That could offer her some rest

 

[Lauren4events]

Do you have another tank where you could move the harassed female to? That could offer her some rest

I have a 5 gallon with a ton of new born red velvet swordtail fish. They are too small to be around her. And then I have another 50 gallon with very large adult fish. She's so small compared to them. I'm afraid that would just cause even more stress. I suppose I could get another tank. But 3 is already too many... Any idea why this happening or how I can slow down the aggression?

 

[evil wizard]

I have no idea why they are ganging up on this one particular fish, maybe there is just somethin about her that they all like.
You said a 50 gallon? Hmm, would it be possible to divide the tank with a divider and then put something in front of the divider so the molly could have some space to her self?
What is in the 50 gallon?

 

[Tifftastic]

I think a divider is a fantastic idea. There's a very real chance that she is the only one who is sexually mature out of all the other females. Is she the largest? I know you don't want more tanks, so getting rid of fish might be the best idea as these ones are just going to keep breeding and so are the older ones.

 

[mrmujtaba07]

There are many reasons to mollies aggression some if them I wanna list here

1. Tank size and set up
2. the ratio of sex in tank

The tank size can be a good reason for aggression, let's say if you have a tank that contains few gallons and don't have enough space for swimming can encounter you in many problems. They need much space to live in a tank. The recommended tank size is 50 gallons if you can afford otherwise 30 is OK. They need planted tank full of many aquatic plants in it so the fishes can hide under them.

Other Reson for aggression can be the sex ratio in the tank, You must have 4 females with one male fish in the tank so they will not bother a single female and lead to a happy community, One of the main reason is to divert the attention of male from a single female fish