I'm definitely not an expert but it has been my practical experience that fish will darken and show their true colors dependant on water clarity. I have bass taken from a crystal clear pond showing all the markings and color and put in my pond which is not super clear and the colors fade when I've caught the fish again. We catch bluegills and hold in a basket until cleaning and while in the basket which is in shallow clearer water they darken and their color gets very vivid. Maybe one of the experts can expound on this.
BMorris
