Difference Between a Male & Female Betta

By Jo Chester

Bettas are domesticated freshwater tropical fish derived of a native fish of Thailand. The wild bettas are less colorful and have smaller fins than the domesticated variety. However, the differences between the sexes remain in the domesticated bettas, even if they are less pronounced. Bettas are commonly referred to as Siamese fighting fish due to the males' aggressive nature.

Betta Splendens

Betta splendens are popular tropical fish, readily available in pet stores and department stores throughout the country. Bettas are easily recognized due to their bright coloration and flowing fins. They are not community fish. Male bettas cannot be kept in the same tank as one another, as they will fight. Opposite-sex pairs can inhabit tanks of 10 gallons or larger. Bettas feed at the water surface, rather than feeding at the bottom or the middle of the tank. They live an average of two years in captivity.

Color Dimorphism

In general, domesticated male bettas are more colorful than female bettas. Wild female bettas are typically brownish in color; however, domesticated females have been bred in colors similar to their male counterparts. Male bettas begin to take on their more colorful appearance at about the age of 3 months.

Fin Length

Male domesticated bettas were bred to have a variety of elaborate and decorative dorsal, caudal and pectoral fin shapes, but you won't see them until the males are about 3 months old. Female domesticated bettas retain fin shape similar to the form of wild bettas.

Although the differences between fins are most pronounced in ornamental types of bettas, the differences to some extent are still apparent in the wild form and in the domesticated plakat variety, whose fins are similar to those of the wild form.

Habits and Behaviors

Male bettas are aggressive to other fish, particularly to males with long and trailing fins, whom they might consider rivals. Female bettas can cohabit with other fish. They can also live singly or in groups with one male betta.

Male bettas are responsible for building and guarding the bubble nest in which a pair’s eggs are stored after spawning. The male also catches and returns to the nest any eggs or newly hatched fry that escape the nest, which he will do until the fry are swimming on their own. The female betta is not part of the process after laying eggs.