Today I got the last two fish I needed to have five for my sorority. Everyone is mostly ok, but two of the fish are causing trouble. My blue girl, Mystique(my first Betta), chases around some of the other girls, but is really, really aggressive with Phoenix(my red and blue one). I have a video here after I separated Phoenix and Mystique. I put Phoenix in a cup(my sister said she started the fight, but now it seems that Mystique is also very aggressive, so I don't know). I don't know what to do! The other three are not very big and they're alright with each other. Mystique is causing all the stress in the tank, and I don't know if I should take both Phoenix and Mystique out of the tank for the night? Should I just let them fight a little because it's supposed to be normal? I think both Mystique and Phoenix are the alpha's. I really don't want anyone hurt, and Mystique keeps flaring at everyone. Right now I separate Mystique and Phoenix into cups and put them away from the tank. The other three girls are doing fine. What do I do about this? Just keep them out of the tank and try again tomorrow?
Please help, thanks!