Sexing And breeding zebra danios pls help

[bjtaylor]

Ok so I recently purchased 6 zebra danios and have decided they are the first fish I would like to attempt to breed, I have read a few things about placing pairs into a breeding tank, how do I know when they have made a pair, or should I just put all 6 of them in? Also how do I know for sure I have females or males, they say the female has a larger belly but the move around so god **** fast in a 90g it's almost impossible to tell what try look like. Any help is greatly appreciated

 

[Samzter]

once mature, females are deeper in the belly than males.

 

[Samzter]

I'm also guessing they like hard water and a lowish temp?? I could be wrong but most danios like cooler water. hope I helped