African Cichlids - Beginner

Question
I have seven African cichlids.  I think that four of them are "red zebras," and the other three I can't decide.  At any rate, they were all in a 20 gallon aquarium when I got them.  The biggest is about 3 inches.  I separated them because (4 in the 20 gallon tank, 3 in a ten gallon)  one of them started failing, maybe due to aggression.  Now all but three of them (two in the big tank, one in the small tank are okay) are hanging around the top of the tank and they just don't look right.  Water conditions are fine (no ammonia or nitrites, PH 7.5, GH 13).  What can I do?  

Answer
Hi Maggie,
 Sorry for not answering sooner -- I was at the national cichlid convention in Denver and just got back.

 There are two main possible causes: aggression or water issues. The best way to distinguish these is to spend a little time watching the tanks.  Is there one fish that is being highly territorial, chasing all the other fish in the tank? This is quite normal for cichlids and could easily explain what is happening.  There really isn't a lot you can do other than remove the aggressor permanently or at least for a little while to allow the other fish to regain some
strength and confidence.  This is one of the problems of relatively small tanks, namely that a fish that being chased has no place to go, unlike in a much larger tank or in the wild.  

  Alternatively, there could be something wrong with your water, but in that case, it would likely affect all of your fish (though not necessarily -- stronger fish might take longer to react). Given that you have tested your water and it looks good, I think we will have to conclude that water isn't the problem, but keep an eye on things, particularly if the tanks are relatively newly set up, as in the last month or so.  It takes about 6 weeks or so for the water chemistry of an aquarium to stabilize.  

-- Ron
  rcoleman@cichlidresearch.com
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