Female Molly

[xlittlestar]

I have a large white female molly and i did have a smaller black male molly which died a few days ago. I have noticed in the last 2 weeks that 2 platy, 1 guppie 2 western rainbow fish have died for no apparent reason. They were all happy and seemed very healthy, i did a lot of water tests but everything was fine so i decided to film them off and on during the day and night. I saw the molly constantly bullying all the other fish but i never saw her doing anything other than that until today when i saw her swim quite fast into the side of a rainbow fish killing him out right. I dont have a lot of fish left in my tank (not that i had many in the first place) i have a 120l tank, any ideas what i can do with this fish im to afraid now to restock knowing that its her attacking them all.

 

[Blitz]

So you said your fish kept dying after that one fish died. Did you do a 50% water change when that fish died? If you didn't, probably the water was contaminated. You might have to separate the fish... Do you have a quarantine tank that you first used? Maybe you can use that tank.