Crossbreeding?

[Heather15]

I have 2 blue platies* 1 male and 1 female* and i have 1 female red wag platy.* im guessing thats what she is* and a black molly. all in a 10gal tank. And I was woundering if they will all breed with each other or would i need to get a male molly and 1 more female molly? for my 10gal. for breeding

 

[Tempestuousfury]

The platies will breed together, since they are the same species.

The molly, however is of a different species and genus, if not subfamily (not sure about anything past the genus, though), so the molly will not breed with the platies.