White worms are too big for betta fry. They can only be fed to juveniles that can eat adult sized foods. They are great adult foods and great for conditioning however.
A mid-sized option is grindal worms. They're kept similarly to white worms but don't get as big.. they can usually be fed to fry around 1-2 months old (dependent on the size of the fry). However it should be noted that some believe grindals to be too fatty to be a staple diet for fry.
Ok i was able to trade some microworms for some white worms acouple days ago.
Even if i shift through for some of tiny ones will they still be too much for the fry well the largest fry? I have tried to look for grindals but there are non in my area and i cant find anyone who will ship them.
I hope to get some pictures up again of the fry if they ever keep still
You can try them, as long as the fry can fit them in their mouths. Personally I'd set your culture up and let it grow for a couple months and use it to feed your adults. They'll go absolutely nuts over them.