Their fin damage isn't actually too horrific. I was expecting much worse.
It looks from the video, like you have a lot of open space at the front of your sorority. You should definitely look at putting in a few more plants to provide more cover and obstacles.
You want it to be extremely hard for a female to get from one end of the tank to the other because that way it is more difficult for them to start chasing a weaker fish around.
You want to add alot more decor to break up their line of sight.
As for the blue one, she may be turning white because of stress. I have a royal blue CT male and his entire body can turn grey, which always freaks me out. He does it every time I change the water.
Stress coat at 2X the doase can help fins heal and so can krodon fish protector.
Also are you sure all of them are females? I had a very young VT female turn into a 3 inch male. I got lucky with him and he was pretty mellow and lived with the girls for over a year ( I recently removed him due to some kind of illness in their tank and didnt want him getting whatever it is) but normally as males get older they get more aggressive.