A Fantail, is a rounded delta tail. It looks like a fan with rounded edges (unlike the delta which has sharp edges).

Fantail Betta
My cambodian flaring 1
Originated From: Thailand
Approximate Petstore Cost: Not Sold In Stores
Fin Type: See Below
It is much wider at the ends than it is at the base, resulting in a tail that spreads out open beautifully. If you divide the tail horizontally with an imaginary line, you will have 2 symmetrical parts. Again, there is roundness of the edges. The tail angle may be wider or narrower, depending on the quality of the line.
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