Betta’s, like many other tropical fish can be kind of picky when it comes to their food but this is all in how you feed them. There is a huge variety of food available when it comes to feeding fish. A lot of this will depend on your budget but here are some your choices. This will depend also on the personality of the fish but here are a few tips on how and what to feed.
Flake food is an option but it is a cheaper option along with pellets. If you start a fish out on these foods it will become accustomed to eating them and will not have any problem with it. However, if you start introducing other foods in that wire potentially more “flavorful” you may find that it won’t eat the pellets or the flakes anymore. These basic foods provide on the nutrition that bettas need and some more extreme data collectors think that’s these foods are a little too basic. That is not true, is purely opinion. Many of my friends have raise fish for their entire lives on pellets and have lived for healthy lives without any dietary issues whatsoever. The choice to go to a more expensive food is purely that of the owner and is usually the caretaker of that tank trying to humanize their fish in providing a diversity of diet. That is not to say that the fish do not benefit from a diverse diet or higher protein diet but is not necessary is a matter of choice and if you can financially afford it go for it.
Freeze-dried and frozen food are also an option. Things such as blood worms in squid are now being packaged and frozen and can be kept for extremely long amounts of time and can be bought for reasonably cheap. They come in individual size packages so you don’t have to use all of the at once only, as you need. If you really want to see your tank come alive at feeding time there is a combination of blood worm in squid cubes that can be acquired at most pet stores or specialty shops mix that in with a little bit of garlic and microwave to a warm temperature and your tank will go crazy in feeding. That was an old trick when working at a pet store that my coworkers showed me to get some of our more lethargic fish to eat. Even after the mixture has been made if you make inner resealable container you can put in the fridge and will last for several weeks after that. Bang for your buck you can’t go wrong!
Another option are things like insect larva such as mosquitoes. While these are option they tend to be kind of expensive and very hard to acquire. Mosquito larva specifically is actually the natural diet of betas in Thailand betas zip up to the surface and eat the mosquito larva that are laid in their bodies of water. And before any of you think “well I’ll just go out and get my own larva from the pond my backyard” you never know what chemicals have been placed in there and you run the risk of contaminating or even killing your entire tank.
Having a primary as well as a backup food is a very good idea. I say this only because many of the more exotic foods come from far-off places where they are more subtle to things like natural disasters. You may find that the normal food that your feeding your beta is no longer available for extended period of time. So if you don’t have a backup food you may find that moving your fish to another type of food may be time-consuming as well as frustrating. So basically having a rotation of foods and some diversity in what you feed is a good idea from a long-term perspective.
For more information on betta fish food, read this article.