Platys have a reputation for being amiable fish that get along with each other. Only when you introduce two males to a tank would you normally see any sort of aggression. ... These varieties have been known to be aggressive at times, but it is rare.

Are platy fish fin nippers?

Fin Nipping

Some platies, especially males, are known to fin nip. ... If you notice a platy nipping your bettas fin then you're going to have to remove it from the tank.

How many platies should be kept together?

How many platies should be kept together? A group of three to six platies is a good starting point. As with most livebearers, the males constantly want to mate, so try to keep at least two females for every one male to give the girls a break.