Delta Betta
Betta splendens
About this strain
The Delta Tail has a caudal fin that fans out in a triangular or wedge shape — wider at the trailing edge than at the base — but spreads less than 180°, typically between 120° and 160°. It's a step between a Veiltail and a Halfmoon in structural terms. Edges should be straight and clean, not rounded or jagged. Deltas are more structurally sound than Halfmoons, with a good balance between visual impact and fin durability. A nice mid-tier choice for hobbyists who want a showy fish without the extreme maintenance demands of a Halfmoon or Rosetail.
Origin
The Delta Tail was defined and standardized by the IBC as a recognized show class to describe bettas that approached but did not reach the 180° Halfmoon standard. The classification emerged alongside Halfmoon development in the 1990s.