Female festae are really mean. IME, when they want to breed, they will "test" out potential mates, even other species. What I mean by "test" is that will put an arse whooping to see if the males are good enough. I had a 9" F1 female destroy a wild caught 12" oscar, who died a few days later, injury a same size male peacock bass to the point of swimming bladder issues, and shred a same size male GT. The only fish capable of holding their own against her is my female 12" Atabapo pike and a 12" male jag. They both have twice the mass of her, and she knows not to even mess with them. This was all in an 8 foot tank.