How to Tell Male Bettas From Female Bettas

Betta splendens, the Siamese fighting fish, are gorgeous and interesting fish. They're easy to keep and they have very individual personalities, and so they are extremely popular as pets. Male bettas are usually the more beautiful and the ones more often sold in pet stores. As the fish has gained popularity, people are more interested in the females for breeding as well as for their interesting personalities. So females are appearing for purchase alongside males. Bettas are well-known for their ability to survive in tiny bowls, but those are not the best habitat for your betta. A well-kept, larger container with a filter is much better and will provide you with a more interesting, active pet as well.

Things You'll Need

  • Known male betta (optional)
  • Known female betta (optional)
  • Mirror (optional)
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Instructions

    • 1

      Compare the size and body shape of known males and known females to your unknown fish. If you don't have any known betta fish, use good-quality pictures to compare to your fish. The males tend to be slightly bigger with a more elongated shape.

    • 2

      Look at the fins. Male bettas generally have longer, flowing fins and tails. The females often have more rounded, shorter fins.

    • 3

      Check the colors. The males typically have deeper, richer and brighter colors than the females, although female bettas are also colorful.

    • 4

      Place a male betta in a separate container next to the unknown betta. If you don't have a known male betta, place a mirror next to the container. Males tend to flare, fully extending their fins when they see another male. While the male is flaring, the operculum, sometimes called a "beard" because of its location, is very visible. In males, this gill cover tends to stick out a little even when the fish is not flaring, and in females it is usually not visible unless flaring. It's a myth that females are unaggressive and don't flare, so flaring or aggressive behavior alone does not always indicate a male betta.

    • 5

      Look for the ovipositor. The most accurate way to determine if your betta is male or female is to notice the presence of the "egg spot" or ovipositor on the female. This is a small white spot about the size of a grain of salt, from which the eggs come. It is located on the underside of the female, between the ventral and anal fins.