Mine were breeding like rats. The male does all the work.
THe hardest thing for me was getting Daphnia for the fry to eat and resisting the urge to clean the breeding tank all the time!
I've since gotten rid of my setup but I built a breeding tank with a sliding glass pane that separated male from female until they were ready.
The pet shop wouldn't buy them and my friends would turn off the lights and hide when I came round with anything in my hands so I gave it up.