I had a male convict in a 55g for about a week, and I just added a female. It's chasing her around and his gills seem to be popping out a bit. Should I put the male in a 10g for a few days? He's ~2in so I think he'll fit there
give him time. if it gets really bad seperate but i don't think it's anything to worry about if you are sure the other is a female. but it don't sound like a bad idea. or try this... take him out for a few days, rearrange the tank and throw him back in. it will make new territories and he might be very passive.
It's natural cichlid behavior, but i think she will benefit from the male going into the 10g for a week. So then she could establish some territory. Then when you add the male back into the tank she would have the upper hand.