Why does my red parrot periodically get black on its finn, tail , body, and even eye?

[jfinn-irwin]

Thanks. Strange thing is, tonight I just noticed them making a nest in the substrate. This would be the first time. I still wonder about the relationship to spawning. Could bad water conditions affect fish like bad conditions do plants? Plants in distress often produce flowers in a last ditch effort to reproduce. This is especially seen in plants that are not known for flowering.