How to Tell the Difference Between a Girl & Boy Goldfish
- 1). Look at your goldfish. Boys will tend to have a longer, thinner body than girls.
- 2). Examine the fins on your goldfish. A boy's pectoral fins will be more prominent and angular than a girl's, with white bumps to the front of the fins.
- 3). Study the shape of your goldfish's body. The female's abdomen will have a softer or possibly lopsided appearance. The male's abdomen will be harder and more symmetrical.
- 4). Check your goldfish's vent. This can be found on the underside of the fish, just in front of the anal fin. A female goldfish will have a vent that is more noticeable.
- 5). Inspect the gills. Boys will have white pimples on the gill covering.
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