Bettas are carnivorous. In the wild, they live off of insects and their larvae. Their mouth is designed to snatch prey on the surface of the water, and their digestive tract is too short to metabolize most plants. This means they are best suited for live food, but they can adapt to flakes and frozen or freeze dried foods.
If flake food is used, it should be supplemented by frozen, freeze dried or live food.
Brine shrimp, Daphnia, plankton, tubifex, glassworms, and beef heart are all good choices to feed Bettas, and are commonly available frozen or freeze dried. Note that Bettas can take up to a week to recognize a new food type, so you should keep the staple food constant and supplement with treats and other types of food occasionally. Most appear to prefer a mix of brine shrimp and bloodworms for their Bettas.
There are dedicated Betta foods on the market. These are usually pellets and should float on the surface for easy consumption. Hikari Betta Bio-Gold is well regarded, as are HBH Betta Bites and San Francisco Bay Brand Betta Food, which is essentially freeze dried bloodworms. Other brands have complaints about Bettas refusing to eat, inadequate nutrition and sinking pellets that Bettas can’t consume fast enough.
With the Hikari Betta Bio-Gold, there are complaints about the packaging, but the larger sizes are easier to use. Remember that each Betta only needs about three pellets, and overfeeding will result in contamination of the tank. This is both because of food that rots and excess defecation from the overfed fish.
Some Bettas won’t eat bloodworms, while others adore them. However, bloodworms are not a complete diet, and should be used as a treat or supplement for those fish that appreciate them. Most say their Bettas prefer live food, but some believe that too much live food can be bad for a Betta.
Let the Betta see the food coming. Drop the food right in front of the fish, so he doesn’t have to hunt for it. If the food isn’t eaten immediately, you should wait for the fish, but if it isn’t consumed in 15 minutes, remove it and try again later. Start small, perhaps 6 brine shrimp, and if the Betta eats them all and there is no sign of belly distention, and the fish still acts hungry, you may feed it a little more, but the second feeding should be smaller.
There are products marketed at Betta vacation foods, but results are mixed. Some appear to swear by them, while others complain of the overfeeding issues listed above.
Additionally, many fish foods claim to be color enhancers. It appears the actual importance is proper nutrition and good conditions, so any good source of nutrients would be about as effective in color enhancement as any other.
Adult Bettas can be happy with feedings once or twice a day, provided care is taken to present a balanced diet and the correct amount of food is provided.
For more information on betta fish food , try visiting the Betta Fish Center (bettafishcenter.com), a popular website that provides tips, advice and resources on caring for betta splendens.