How to sex them is explained by Matthew. There's just one thing to add:
The males are more colourful.
I've bred them in the past in a normal community tank. But it was just a
mistake :-). I had to take all fishes to another tank and leave that
tank running without fishes. A few days later there are a lot of small
fry.
Later I knew, that it were the Celebes Rainbows (Telmaterina ladigesi).
So it should be easy to bread them. There were no mops in that tank and
also no moss or anything like that, just plants with bigger leafes.
So maybe they don't need any special breeding places, I don't know.
Karsten