How can you tell the difference between male and female pearl scale goldfish?

A male goldfish is a little bit bigger than a female. (sometimes this is not true) It depends how much you feed them Sexing Goldfish outside of the breeding season is extremely difficult. In the breeding season males develop small white pimples (breeding tubercles) on their gill covers and along the edge of their front fins (pectoral fins). Females are generally more rounded and deeper in body shape as they fill with roe (eggs) and have a larger vent before the anal fin.