Before and after goldfish? What happened?

Question

I thought It could be ammonia burn so I been treating but I don't think it is since it just get's blacker no matter what I do and it swims and eats fine, he's got quite the appetite. It is in front in the first picture and bottom right in the second picture.

Update:

I meant to say she because it's a female so I'm also wondering if it were to get lay eggs would the babies be black too, I think it's cool I've never had a black goldfish.

Answer 1

Favourite answer

Goldfish change colors like this sometimes, nothing to worry about.

Answer 2

There is only puranas.