Sarasa Comet Goldfish turning completely white :(

Provided the color change has happened naturally (he's not sick, injured, etc.), no you cannot stop it.

... and yes, they do seem to have red in their eyes. My Goldfish all seem to have that red reflection in the lights.
 
My comet was a beautiful bright red/orange, my mum would say how beautiful and big and healthy he looked. Not so long after(when he was about three) He changed to a white colour! It was almost as if it happened over night!

He still looks SO healthy though. I thought I had done something wrong too, but I looked it up on the internet, and although they can turn white because of lack of light, some would do this no matter what the conditions they are kept in.

I have had other goldfish turn white too!
 
yea they change colors all the time, well not all the time but they do change and patterns can come and go. my koi do that i had some that i thought would be some show winners till they decided to change their looks, how come they never change to look good in the eyes of us humans. get some bird netting for the pond that helps keep mine clear and some sunlight is good their oranges and reds will get really rich and dark that way, just keep some of the hyacyths there at all times for shade incase it gets too hot/sunny.
 
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