Fish behavior

Question
Sir,

I have a fish that has been exhibiting unusual behavior. It is a jack dempsey at least 1yr old, and about 4-5in in length. It is one of 3 dempseys and 3 pacus, 1 red tail shark (small) and one algea eater, living in a 75 gal community tank that I maintain carefully. For the past few weeks this dempsey has remained hidden. He appears to have a sort of "dormant" attitude. He picks a hiding spot, and just hangs there. Very little movement, and very minor reaction to external stimulus. He moves around the tank to different hiding places, but has not come out in over 2 weeks. At first he appeared to be dying (I have seen similiar responses before), glazed eye look, roughed up patches (small) on his body, no movement, shallow breathing, wont eat and so forth. his appearance is better now, clear eyes, body healing and such, but still remains hidden.

This behavior apparently started shortly after a tank cleaning. All my other fish reacted normally to this cleaning and are healthy, active and vigorous. But not him.

I have a 75 gal freshwater tank, I maintain properly. It has been operating for several years. Their are only 7 large fish (4-5in) in this tank and I see no problems with territory or aggressiveness towards each other.

I have not tried any medications or isolation (dont have an isolation tank and dont know what medicines to use anyways).

Please respond with further details you require to fully understand the situation and environment and I will provide it. I would not want to lose this fish. Any information would be appreciated.

I await your response.
Sincerely,
Randy Martin  

Answer
Hi Randy,
 It sounds to me like the other fish pick on this one and he hides to avoid it.  The best solution is to provide lots of places that he can take refuge in if he needs it.

-- Ron
  rcoleman@cichlidresearch.com
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