I've heard, but have not had experience with it, that Bettas a lot of times won't eat the flakes. I feed mine the Top Fin Betta Bits 4 days out of the week, fasting one day, frozen blood worms on one & frozen brine shrimp on the last day and so far they eat EVERYTHING like they're starving. I may be wrong but my understanding is that the frozen bait doesn't meet all of their nutritional needs which is why it's only to be fed on occasion. Personally, I would try a pellet. All of mine will eat as many pellets as I drop but I limit them to 4 at the most. I like the pellets because I drop one see who eats it then drop another in front of who hasn't had one yet (works most of the time, but sometimes there's a bully
) I can control & monitor their eating & there's no waste because each pellet gets snatched up. I also have Wardley Pellets & nobody will touch those but the Top Fin they gobble them up. I have 6 Bettas; 4 female & 2 males.