On occasion I usually feed my cichlids and loaches a sliver of banana and they love it. Yesterday I was in the betta room doing some things while my kiddo ate a nana, she asked if I'd give the rest to the frontosa and I told her she had to wait just a minute but that I would. She then asked if maybe the bettas would want it. I used to feed them a tropical frozen food with bananas and they liked it so I told her to go ahead and throw a chunk in the red tank. She did and they went bonkers for it. They ate every last sliver.
It would probably be hard to feed it to individual bettas, but if you have a female community it might be worth a try as a treat now and then.
