I saw this show once whereby these guys in a lab were breeding goldfish (in aquariums) by simply adding a mop end to the tank during the night, and removing it early in the morning with the eggs attached.

just thought I might share that for any would be goldfish breeders.

I saw another one whereby the guys were manually squirting the eggs out (and milt) from the fish by gently adding pressure with their hands (thumbs). I actually tried this years and years ago, without success.

I do not know if the fish were mature enough for it to succceed - I was only 14 years old. :?