How Do I Breed Balloon Mollies?

[bluesword23516]

I have never bred mollies before and I have a few questions.
 
My mollies are balloon mollies.  I have two females and one male.  He usually tries to breed about once every 3 days. Not as much as I would like to breed the females, but it should be enough.  Anyways, the females haven't gotten pregnant, why?
 
Also the male is about 2 inches long and about 1 inch high. (probably a little shorter) and the females are only about 1x1.  are the females too small to breed?
 
I want to crossbreed them with a different breed of molly, what would be the most successful? 

 

[the_lock_man]

It's always difficult to tell whether a balloon molly is gravid, because of the malformed shape of the belly.
 
It may well be that they are breeding successfully, but you aren't seeing any fry because they are being eaten straight away by the adults. Livebearers are a bit daft in that respect, they'll happily predate upon they're own fry.
 
Do you have any/many plants in your tank?

 

[bluesword23516]

Not a lot, but I have multiple other livebearers, but I haven't seen either female go into labor.