I had some fry in the two years ago. Some of them changed colour within a
few weeks, shubunkins first, then goldfish. But two goldfish were still
brown this year

I have a 4 year old shubunkin that is still black....He has a very few gold
scales.....sort of like a ginrin koi. I have had goldfish not turn for 2
years. I also have a few in the pond this year that are already turned at
less that 1/2 inch. It just seems to depend on the individual fish in a mixed
pond Jerri

http://www.fringeweb.com/Ponds/JerrisPond