Im at a loss here on what to do. I have 4 orandas in my 75 gallon tank.

I have currently separate my "black oranda" to a 30 gallon. I’m not sure if this was the right move. The problem is he sort of bites everyone’s vents and then they hand upside down. Im not sure if I should have let them be and work it out. He would also bite their sides.

I just get really paranoid when I see aggression of any sort. He is a little bigger then the others. When he did this they looked uncomfortable and kind of backed away when ever he came near them.

Should I have separated him? Will he hurt them if I try him back in the 75 gallon? Is this “normal” goldfish behavior? Do I just ignore the aggression?
Sorry I have so many question but I really need some advice here.

I've had the same problem, in the end I’ve had to separate my males from the others too. I'm of the opinion that you have to do the best for the larger good. It was too stressful for my girls to be chased all the time and my male had damaged his eye.

They all live happy lives now, and the male loves the room he has.

now i feel better knowing im not the only one with a meany my new oranda that i believe is a male is very aggresive also. ive had to take all my fish out cuz he likes to bite? the wens and around the eyes i think separating was a good idea