Above is water flea 's picture.The best food for fry (baby betta fish) is water flea because water flea has a lot of protein and digestible. Fry love to eat them. It is the main food for growing up baby betta fish.
Water flea is very small size. I usually use for feed fry when they are 7-10 days old. I feed baby betta fish with water flea for 3 weeks after that ...I feed baby betta fish with red water worms.
In Thailand , I can buy water flea easily. I think if I cannot find water flea , I cannot raising betta babies. It is very important!!!
But if you cannot find water flea...I have another food for betta babies. It may not good as water flea but you can raising the fries with this food ,too. It is "artemia's eggs".
For more details about artemia's eggs. I will explain how to use it for babies betta later.