Well goldfish are a member of the carp family, and as such are entitled to be Mudcatters, where carping has been raised to an (f)art form by some.
Then there is the Golden Orfe which is a large gold fish, and may have got that name because it farted a lot, and people kept telling it to Fuck Orfe.
Then there is the Shebunkin Goldfish which is such a silly name that it might be best if I didn't go there.
At least Goldfish only have one bottom to fart out of, so be grateful folks