Got a pet goldfish and looking for the best name for it? Well, you might want to figure out if it is a boy or girl first. Here’s how to determine if your goldfish is male or female.
Study their body shape
Male and female goldfish differ slightly in the way that their bodies are shaped. Females are rounder, thicker, and longer. If the fish are breeding, then the females will have a protruding anal opening. You can identify this by looking at the fish’s abdominal area, beneath the anal fin.
An easy way to identify males is by looking for white spots along their gills. These are called tubercles. Males also have visible midline ridges, which are along their bellies.
Pay attention to behavior
Female and male goldfish will behave in different ways, so it pays to spend some time observing your fish. If your fish is following another goldfish around, then it’s probably a male. During breeding season, the male goldfish will chase the females and nudge them against a wall or tank accessory to mate.
The easiest way to identify the sex of your goldfish is if you have two or more fish in your tank. The breeding season for goldfish is in the springtime when the temperature is warmer. If you’ve only got one goldfish, it’s going to be much more difficult to accurately determine their sex.
Wait until the fish are mature
You will have a much easier time figuring out the sex of your goldfish if you wait until they have matured into adulthood. Don’t worry, it only takes a few months for a goldfish to reach maturity. In the meantime, keep them healthy and well fed because it’s much harder to determine the sex of a malnourished, dirty, and sickly goldfish.