In a 70gal, they have enough room to set up territories far away from each other and basically never see each other. In a 29, they don't have that luxury. I would say to leave one in your 70, preferably the maroon, and get another fish like a percula or ocellaris clown to go in the 29. I have an ocellaris and a lemonpeel in my 29 and they get along just fine.