The Doubletail

Blue Doubletail male (DTM)

The Double Tail betta is also known as DT or DTM (doubletail male), and DTF (doubletail female). They are a cultivated mutation that gives the fish a dorsal fin equal in length to the anal fin, and two distinct caudal lobes. Often it also produces a thicker-bodied fish with a wider backside, or deformities such as crooked spines.

Breeding DT into regular ST or HM lines is widely practiced because of the advantages the gene brings, such as wider dorsals and better branching. It is always recommended to cross DT to a single-tailed type only, since DT x DT often produces deformed fish.

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