Black Mollies appear dull in color, is this normal?

Question

I have a marble molly and a black molly that has me a little concerned. The black molly isn't shiney, his black coloring is sort of dull. The marble molly I had remembered her being really shiney with her black, silver, and small amount of orange coloring on her scales. As she's grown to nearly fully adult size I've noticed she has turned almost entirely black now, but she has lost her shininess at least in the areas that are black. What remaining silver coloring the female molly has does still appear glossy/shiney though. Any scales that are black on her body appear dull, just as the male's.

Is this normal for the black coloring to appear dull? Other than the coloring I really have no other concerns about them, they other wise appear and act very healthy.

Answer 1

The fish food you are feeding them may not be fresh, or may be lacking vitamins or pigment inducers.  Also, check your filter to make sure that it is flowing properly to bring oxygen into the aquarium - that may help a little.