Considering the numbers of fry that one spawn can incude, (hundreds) I would see that I had numerous plastic tuppeware containers to house the males and I would make sure that I had a demand for the babies.
The freeze dried bloodworms are the worst things you can feed them it has no nutrional value. I would suggest a variety of frozen foods. Also you will have to have a heater to keep the fry warm when you move them into there individual containers. To achieve this I would get a big cooler and fill it to were it will be close to the top of the containers the baby bettas are in and place the heater in the water with a small internal filter to keep the water moveing around the small betta containers. And you will have to do water changes on all the little containers so that the fry stay healthy.