I have had two clowns for severals years now. They use to fight all of the time. The first week I had them one did become ill but recovered. I put them back together and they continued to fight but the smaller one never became ill again. They still fight off and on, however, it is much better. When I got them they were about the same size, very small. Over the past three years one has grown large while the other stayed small. I hoped this would happen. I think they might have laid eggs this week.
They now pick on me more than each other. I can not put my hand in the tank near their hammerhead coral.
So I would give it a try once the one in the Q tank is good and strong. I do agree that rearranging the tank is a very good idea.
Good luck,
Connie