I'm not positive mind you, but I asked an employee of Petco about their shipments when ours had an entire aisle of bettas. (before the remodel) They said the bettas come in, in tiny triangle bags barely bigger then the fish. (I know that isn't really specific but I have never been allowed to watch a shipment being unpacked... I asked though, lol)
One of the Thailand sellers on Aquabid has a video, and shows the small shipping bags and the machine that seals them too, as well as details on their care on a fish farm. I watched the entire thing although I couldn't understand any of it, it's in Thai, it was still interesting to see how they worked the farm to me.
I don't know where I came across the info anymore but if the fish you got were half moons I read it's pretty common to have them bite their fins in the tiny mass shipment bags. In the tiny bags before the transhipper gets them, their fins are right in their face and the stress of shipping can cause them to bite them.
If I can find where I found this I will PM you the details. I lost the contents of my HD a while back from reinstalling Windows so I don't have old things saved anymore. At the very least, I'm sure I can find you the aquabid video though.
I hope your new boy stops biting his fins though. :(
Betta Fish are like potato chips, it's hard to have just one!
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