swollen bottom lip

Question
I have a red-bellied pacus that the bottom lip became very enlarged. It started about 2 days ago and was huge today. I had noticed that the water had started to become cloudy so I cleaned aquarium and now the lip it almost back to normal. Do you think it could have been lack of oxygen or something in the water, I had noticed that all my fish were staying at the top of water, which is not like them at all.

Answer
Hi Dustee,
 Hmm... that would be very unusual for a lack of oxygen to cause an enlarged lip.  The fact that they were all staying at the top of the water suggests that your tank really needed a cleaning.  

In general, you should be changing 25% of the water in that tank once a week, every week to keep your fish happy and healthy.  

-- Ron
  rcoleman@cichlidresearch.com
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