green/turqoise severums

Question
hello, i have 3 "turquoise" severums obtained from a chain petstore. they range in size from about 2 inches to 3 1/2 inches. they are in a 35 gallon "black water" tank with a large peice of mopani wood, abundant fake plants for hiding, around a dozen mixed danios, whiteclouds and bloodfin tetras, and 2 gouramis, a platinum and a pearl. my largest severum is always dark colored,almost black, occasionally(rarely) he lightens up to allow a black bar to be (barely)visible on his back end, my middle size is always shiny silver with bold black stripes, and my smallest is always brown-ish with a very dark bar by his tail, and 2 or 3 lighter bars barely visible on his sides. at what size do they begin to color up? and is there a reason that all 3 fish display such different colors even though they are in the same tank? the tank has a 75 gallon filter running on it, with weekly water changes and bi-weekly vaccuming. they are fed a mix of tropical fish flakes, cichlid pellets(herbivore and carnivore) frozen bloodworm myosis shrimp and spirulina mix, tubifex worms(freeze dried) and boiled leafy veggies. the ammonia, nitrates and nitrites are 0.

Answer
Hi Robyn,
   I have found that severums use color a lot to display mood, perhaps moreso than many other cichlids (which as a group, use color alot relative to many other fishes).  I have a tank of red-head severums and of the 10 of them, no two are the same color.  In that species, the females go VERY dark (basically black) when they are laying eggs or guarding eggs.  The key thing is that the eye gets bright.  This is in contrast to when they are feeling very poorly, in which case they are dark but the eye is not bright.  

 Bottom line: I wouldn't say that anything is necessarily wrong.  

-- Ron
  rcoleman@cichlidresearch.com
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