[Dmaaaaax]

Color can be based on several factors:

1.) Stress- water chemistry off, or fish being picked on (lighter color)

2.) Mating- certain fish do not show off their "true" color unless it is mating season or unless there is a mate/competition in the tank then they get very colorful

3.) Lights off- Fish will calm down find a spot and rest, when lights first come back on, they are often more pale and take a while to get their color back

4.) Artificial color- some fish, like painted glass fish are injected with color and loose their color over time

 

[Dmaaaaax]

Hey Dmaaaaax you lost me with the statement about painted glass fish are injected with color what is that all about?

Here is a picture of the fish:

They are injected with the dye at several spots. Other fish are dipped in ink/chemicals. These are all artifical coloring that wear off over time leaving the fish looking "faded". This is a cruel practice used on the fish, and I hope no one here gives in to this by buying any....BTW look at that cool Pleco camaflaged right under them!!