Advice please Parrot fish turning Black???

Just Wondering wrote,
But now he seems to be going Black ? , his natural colour
is orange , the last time one of my parrots went that colour they where
about to lay eggs , but this parrot i'm almost certain is a male ? What is
the black colouring he is getting likely to be ?

If it isn't it's breeding color, then the darkening is a symptom of
illness - bacteria infection, due to poor water quality... A loss of
neurological control will/can also make body color darken, which could
be due to brain or eye flukes, inwhich a two day treatment with
Fluke-Tabs would help...................... Frank