Why Do Oscars Change Colour?

[cuticom]

So when I bought him a few weeks back, he was all white and orange with a touch of black on his fins, the tank he came from, had extremely bright lighting, and the oscars spent the entire time underneath the filter.

When I bought him

Now

His new tank has no lighting, as I wasn't planning on plants, and the fish looked fine without the light, would that be whats causing him to turn black? He's got grey patches on hid body as well, and his eyes are black (they were always black)

So is he going to turn into a normal tiger oscar?

 

[Miss Wiggle]

oscars, like many cichlids, use colour as a way of expressing how happy they are, good strong dark black and bright vibrant orange are hat an oscar should be, pale grey or even white for the body colour (unless of course it's an albino) is a sign they are unhappy with something, either tank size, decor, water quality, feeding or unsuitable tankmates.

Also as Oscars grow up their markings will often change and develop.

So I would say the fact that he is changing to a darker colour indicates he is settling into his new home and happy.