Spawns can produce up to 500 fry, more likely to be 100-200 but if 50% are male you would need between 50-100 jars.
One uk betta breeder uses the 4' tank with bottles in it method and he raises some lovely fry!!! Guy called Dave. Lovely line of coppers...
Raising fry with their food needs is quite difficult too. Have a go at breeding livebearers and raising their fry frst. It will be good practise, and if your still interested after that start buying lots of jars!!!
Hope this helps Hoddy.
