Sounds like magis or kat need to hook you up with a flathead for some population controlThe brownish/gold color of the goldfish you are holding is the natural common color of "goldfish". They were selectively breed in ancient China to achieve the colorful oranges/yellows/reds that we have now....i.e....when they'd get a orange one they'd remove it and only breed it with another orange one to increase the chances of getting more orange ones. I have a pond out back that we use as a nursery/holding pond for goldfish that we take out of customers ponds when they are over crowded do to breeding. Do to their breeding in my holding pond( I now have thousands of them), about half of the fish in there are the same color as the one you're holding. Left to themselves, over time the % of colored goldfish would decrease and the natural brown/goldish color would increase.