Swollen eyes

Possibly expressing the mutation that was bred into bubble eyes? Not really sure, but it reminds me of a joke.
Q: What do you say to a Goldfish with two swollen eyes?
A: Nothing, you already told it twice!

That's rather odd. Since it's not the eyes themselves that appear to be bulging, I don't know if I'd immediately think it was an illness or pressure build-up. Perhaps it's a phase in the development of the fish's wen?

I do not personally have any experience with this, and it may be just a part of the fish growing but as with anything fishy, the first and most important thing is very clean water. If it is some illness, very clean water will help. Daily water changes. If it is nothing, the clean water will not have hurt. Hopefully Kashta, Flarringshutter, or Lupin...or one of the other goldie experts will chime in.

I saw something like this recently on another forum (for goldfish.) Let me go do some reading and see what they said about it.

EDIT: From what I have found, swollen eye rings can indicate an excess of fluid in the tissues around the eyes, and can be a precursor to dropsy. Also recommended is to up your KH and GH, hardening your water. Using calcium chloride can reduce the effort needed for osmoregulation (water exchange.)

Kristina

Dropsy in of itself is not a disease, but rather an indication of kidney failure due to parasites, bacterial infections, water quality, or other factors.

Dropsy is not contagious, but the factor leading to dropsy can be. I would not treat the main tank unless there are indications that other fish may be having health issues, just observe closely.

Are there any chance of more pictures, especially from a top view?

My first step personally would be to add one teaspoon of salt per gallon to the water in the QT. Other than that I would do what I could to get parameter readings on the main tank to rule out water quality issues.

Kristina