clown having trouble swimming

Question
Tonight, I put a new foxface in our reef aquarium and within an hour, our seven-year-in-tank clown fish started to swim upside down and was fighting to keep from floating.  It keeps anchoring itself under a rock or filter to avoid floating.  Did the foxface cause this or is something else the matter?  It has had no other problems and has been eating well.  Thanks.

Answer
Hi Sue,
 That's really hard to say but I wouldn't be surprised if the new fish had something to do with it.  Reef fish can be very territorial.

-- Ron
  rcoleman@cichlidresearch.com
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