Hi again
I think you need to hold off any ideas of spawning at the moment
If she's been fed bloodworm etc...for a week she should look a lot bigger. I'm beginning to wonder if she is a she?? Or a juvi male?
How we breed - Both male and female are condition for 2 weeks in seperate tanks (female in the spawning tank); then she goes into a chimney and the male added; after a few days when the female is fat and sometimes showing vertical bars we release her.
There's nothing wrong with breeding in a plastic container like you have got, it looks big enough but would just be a little difficult to clean out etc...
Have the bettas got other tanks or are they housed in those bowls? If they are, then i would strongly advise you to get them at least a gallon tank each
The other reason why i say hold off is that are you really prepared for the fry? Could be 100's. And they will all need homes. Your gonna need a big grow out tank for them and jars to seperate them at anything from 4 - 12 weeks!
IMO - get them a couple of nice tanks, enjoy them for a while, and then get everything you need