This is really interesting to me! I have my first pond going and I'm really enjoying it! I have several goldfish that I rescued from the feeder tanks at Petsmart. They were all white and orange combos -- about 2" long when I got them. They are now about 6 to 7 inches long. While most look the same, just bigger, one of them has changed coloration a lot. It was mostly white with a lot of orange. Now it is almost completely white! I guess this is normal? Fascinating!