How do you determine goldfish gender?

Answer:

The sexual dimorphism of a goldfish can only be observed when the fish are in breeding condition (in Springtime) when the adult males develop white spots on their gill plates and sometimes the pectoral fins too. The females just get chubbier around the stomach area.

First answer by EddyJ. Last edit by EddyJ. Contributor trust: 132 [recommend contributor recommended]. Question popularity: 2 [recommend question].