Black convict color change

Question
We have had a black convict for several years and she had been the only one in the 45 gallon tank for about a year. We just added 6 more fish to the tank, a jack dempsey, giraffe fish, tiger oscar, and 3 goramis. The convict has always been the same color, gray with black stripes and orange belly. Today, however, she turned very black. You can still see her stripes and orange belly, but her overall color changed dramatically.  We left for awhile and upon returning her color was back to normal , but she quickly changed to black again.  We have never seen her do this before. It has been about 3 days since we introduced the other fish. What is going on? Is she sick or stressed or do these fish normally change colors?

Answer
Hi Pam,
   Cichlids, and particularly New World cichlids like convicts, use color to express themselves. Very black is a tricky thing to interpret.  It could be that she is being VERY territorial or it could be that she is very scared.   When you say that she is black, do you mean all black or that the black parts have gone blacker but the lighter parts have gone lighter, i.e., she is more
"contrasty"?

-- Ron
  rcoleman@cichlidresearch.com
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