Paratilapia polleni, swim bladder

Question
Hi, I hope you can help me and my show fish, Bo. I have owned this polleni for over 3 years and have been very successful with him in northeast fish shows. He has been best of show several times, one time winning the Innes Competition at the Northeast Council of Aquariums. Because of all this show activity, he has lived alone in a 29-gallon, where he has seemed quite happy. All of my water parameters have always been excellent--I am a big believer in frequent water changes. His filtration now consists of a huge sponge filter and I feed him a wide array of foods, never live, though. He is a real carnivore, but I try to keep the protein to minimum.

Bo is now almost a foot in total length, has a big humpy head, and is otherwise very beautiful, pitch black, bespangled with stars, long trailers. The problem arose when a friend of mine convinced me to let him stay in a 20-long, so as to be easier to travel to the Ohio Cichlid Extravaganza which starts exactly a month from today. Bo hated this tank from day one and went downhill fast. I put him back in his own 29-gallon a couple of days ago and he looks a little better. He has a hard time remaining buoyant. It isn't clear to me if the fish is actually sick or not. It is as though he is still afraid he is going to hit his head on his previous low glass ceiling, as it were. He is eating, and I've begun treating him with Metronidazole, just in case the stress of the past few weeks have damaged his swim bladder. Tonight he seems a little more frisky and is playing with his golf ball. Bo is truly a member of the family, and the shows be damned, I want Bo to live for another 15 years. He is a sentient animal and loves me to pet him; he is totally hand tame. As of this writing he seems to have no problem getting off the bottom in an initial surge of motion, then seems to think better of it and lets his tail drag. What do you think?

Answer
Hi Judy,
 It is really hard to say what is going on. He might simply not like the change from his traditional home. Many large cichlids react that way.   
 Stress cannot really damage the swim bladder directly.  It sounds more like he does not want to swim, rather than that he cannot swim.
Is he looking better by now?

-- Ron C.
  rcoleman@cichlidresearch.com
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