Whole Blood worms may be a bit big for Betta fry to manage but chopped finely they should be OK.
you are going to want to feed them flakes but make sure it is turned into powder you want to crush it up with a plastic knife. this will help them get the food in their mouths after 5 weeks you can...
Any fish fry are nutritious to all carnivorous or omnivorous species. Why should Betta fry be different?
NEVER put two bettas in the same tank no matter what sex they are. they will eat one another instantly.
live micro worms, vinegar eels and baby brine shrimp.
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