Not quite sure why you'd want to use helium, tbh...
Standard bubble machines produce bubbles that are pretty light anyway, and whatever you use isn't likely going to make the bubbles any more controllable so they're going to go pretty much wherever they want once they're created.
In theory, I guess, helium variety may tend more towards going up and not down at all (which of course regular ones will do) but how you'd use helium (on, I presume, any kind of low budget) isn't something I guess that would be easy...