Black Moor changing colors?

[duskiefish]

I have had a fantail Black Moor for the past eight or so years. True to his name, he has been black for seven of those years--but during the last month or so, he had begun turning a quite beautiful golden-color. It started around his belly and pelvic fins, and has been creeping its way up. He now only has a "toupee" of black around his bulgy little eyes and his dorsal fin.

Aside from the interesting color change, the fish is fine. No ich, no dropsy, no tail rot--and I change his water and vacuum his gravel every week. I know it's not a disease...so what is it?

Oh, and as for the specs...
He (I just assigned him a gender, not really sure if its a "he") lives in a freshwater 5 gallon tank. He's been in there for about six of the eight years I've had him. No plants in the tank, and it is assumeably at room temperature because I don't use a heater. He eats Wardley shrimp pellet food, and the last time I did a water test (with the droplets in a sample, not test strips), everything checked out normally. He's the only one in his tank because he's pretty big--about four inches if you count the fan tail.

Has anyone ever experienced or heard of this before?

Here's some pictures...

Dusk in 2005--


Dusk today--


As you can see, the change is quite dramatic.

Thanks!

[Torpedos]

Yes it is.
Most goldfish are hybread meaning that colours cant be 100% gurantee.
But usually they colour up within their first year.
You may just have a late bloomer.
Good work keeping him for 8 years.

[darkfalz]

Nice fishy. Once I am done babysitting the tiger barbs, I'm going to make that 40L coldwater so that it's one less heater that I need. Probably going to go with white clouds but some variety of goldfish might be fun - yes, I know they get huge and are "meant" to have huge tanks, but it might be nice considering most get to live in horrible little bowls and other evil contraptions. Either that or go back to a betta, but it's a shame to waste that internal filter and put in a sponge filter instead.

[emc7]

My sister's goldfish lost color as they grew, one had black spots go away and the other lost its orange and went white before going to a friend's pond.