I read an article about tail biting on bettysplendens.com and I came across this:
"A bitten tail should not be confused with a 'blown' tail. When a male is described as 'blowing' his fins, it is a term associated with the curious abberation that occurs in some heavily-finned males that are swimming or flaring too hard. The webbing between the rays develops pin holes and the ends of the tail begin to fray, like an old flag that has been whipping around in the wind. In extreme cases the caudal fin completely disintegrates, leaving the betta with spikey ray extensions and no webbing to speak of. In its milder form, tail blowing can cause the fins...all three unpaired fins, not necessarily just the caudal...to split along the ray in several places."
This seems to describe my doubletail perfectly. The webbing in between the rays of his caudal fin is disappearing. He swims a lot, flares a LOT and he paces back and forth across the the glass when I come into the room before he calms down after a little while. He is in a divided tank with a veiltail that is also active (with no signs of fin problems). He doesn't seem stressed and there are no plants or sharp objects in there that would tear his fins. It's only his double caudal fin that is affected. I've been watching him for hours and never caught him trying to chase or bite his tail.
Has anyone ever had a betta with a blown tail? If so, what did you do?