Why are my female zebra finches fighting?

Have had two female Zebra finches that I adopted at the same time, and they were in same cage with two other pairs. All got along just fine. I put all 6 finches (3 pairs) in a new, large and roomy flight cage. All was fine for a day, then one of the female zebra finches started chasing the female (the ones I adopted at the same time) and plucked out feathers on her neck. I separated them. The aggressive one is alone in a roomy cage next to the flock. Now a male finch is jumping back and forth on perches (as OCB) and it appears he wants to be with the aggressive female. He sometimes chases the female that was feather-plucked! The other 4 finches treat her just fine. Should I just put the male with the aggressive one?