Zebra cichlid

Question
We have recently set up a new tank (5 weeks) to start the tank off we brought 3 zebra cichlids and we added a few more fish last week 2 red tail barbs a plec and a bristle nose all has been fine but now one of the cichilds has been acting really odd (he was the boss of the tank) but now it just sits on its own up the corner it wont eat been 3 days now, theres no sign of any diseases (white spot) etc.
The fish is hardly swimming round the tank it just moves if any of the other fish come near it, its belly looks a little bloated and has a clear string hanging from it about 3 inches long. any advice would be greatly appreciated.

Answer
Hi Tracy,
  Unfortunately your fish seems to have what we call "bloat".  Bloat isn't a specific disease per se, but rather a description of symptoms, namely acting lethargic, having a distended belly, etc.  Because bloat is a series of symptoms which may possibly be caused by various actual conditions or diseases, there is no clear recommendation about how to treat it.   The fact that there is a clear string hanging from the anus strongly indicates that the fish has an intestinal infection.  

-- Ron
  rcoleman@cichlidresearch.com
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