Goldfish changing colors or fish sitter killed and replaced one?

[MaggstAa]

Long story short, I just got back from vacation, left very specific instructions for the fish sitter and somehow he still messed up, really bad. I had the manual feeder on for once daily and we found out he has been feeding them three times a day. I told him not to touch anything anymore and that the fish could fast for the last few days and eat the plants if they got hungry since overeating can kill them. Well we got back today and the headcount in the tank is still correct, but one of the 8 fish seems to have changed drastically. Now I know fish can become discolored when they are stressed out, but this isn't like any normal fading. Whereas he used to be an overall shimmery brownish-gold with a clear tail, he is now completely matte yellow-orange with some black spots on his body and tail. He is also the only one who has gotten slightly bigger. This may sound idiotic but the reason I am asking is because before I confront the fish sitter and accuse him of killing and replacing my fish I want to give the benefit of the doubt and make sure there isn't some color changing phenomenon I'm not aware of. But as far as I know and in my experience goldfish can only fade or enhance in color but not develop patches or completely change color, especially over the course of a week. Responses/opinions greatly appreciated since I would like to tackle the situation ASAP. Thanks!!

 

[TMaier]

I am sorry I don't have experience with Goldie's. But confronting isn't worth the stress. You honestly cannot trust this person any longer and I wouldn't waste your energy.

Keep an eye out for a fish with the colors you miss and try to rehome ones with colors you do not care for.

 

[Fresh2o]

Goldfish can change colors and shading can appear but this usually occurs over an extended period of time. A week. Hmm??? Smells like shenanigans to me.
Agree with above, no confrontation and no future care.
Excluding fry, hard to feed, and delicate species, fish in general can go without food for a week or two.

 

[idol1]

gold fish do change colors as they grow.

black to gold. Gold to White and gold. black to bronze.

Never had one go to gold to black.

I have black and gold, but they started out black.

I breed gold fish. I agree not worth getting in a fight over.

My goldfish grow fast but only in a pool.

 

[Mpwallace1]

I agree, no confrontation. Who was doing who a favour. Replacing it in my view is him stepping up to the plate and taking responsibility for what ever happened.