Koi
Koi betta is a domestic color pattern of Betta splendens selected to echo the patchwork look of koi carp. It usually combines white, cream, orange, red, and black markings, sometimes with blue or metallic accents, and it is most often seen on short-finned plakat bodies as well as halfmoon or other fin types. Many koi lines are tied to the marble gene, so a young fish can deepen, lose, or rearrange color as it matures. The name describes appearance, not a separate species or a single standardized breed.
For keepers, a koi betta needs the same warm, clean, low-current aquarium expected for domestic bettas, with space to patrol and surface access for its labyrinth breathing. Buyers should judge the fish's body condition, fin edges, and activity rather than expecting the exact pattern to remain fixed. Breeders pair koi selectively for contrast and distribution, but offspring can vary widely, and culling or rehoming plans matter when working with marble-based lines. Males are normally housed singly; females may also be territorial depending on temperament.
Colors: Alien, Bicolor, Butterfly, Cambodian, Cellophane, Copper, Crowntail, Delta, Double Tail, Dragon Scale, Dumbo, Elephant Ear, Galaxy Koi, Grizzle, Halfmoon, Koi, Marble, Metallic, Multicolor, Mustard Gas, Nemo, Plakat, Rosetail, Samurai, Solid, Super Delta, Veiltail, Wild Type