strange tetra behaviour

Question
Hi again!
I doubt that you remember me.  It's been a while, so let me update you about my fish.  I now have 3 zebra danios, 3 cherry barbs, and a glow light tetra.  I use to have 2 tetras, but 1 died instantly and the other thrived.  But recently I've noticed that the tetra starts keeping away to his own little plant.  Even more recently, he started "sinking" in the water.  His tail sank down and he put up a fight to stay up, so he results vertical.  Do you know what's happening to my poor tetra?

Thanks for all your help!!!
Kenny

PS He eats fine

PSS Before this behvior, he played well with the other fish (even the danios!). I don't think he is being bullied.

Answer
Hi Kenny,
  Unfortunately that doesn't sound good.  It sounds like he's losing control of his ability to regulate balance.  There isn't anything that you can do about that. Sorry.

-- Ron
  rcoleman@cichlidresearch.com
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