Spawning is easily triggered by water changes with water that is cooler than the tank water. Next morning after the WC look on the underside of broad leaf plants like swords. They like those. Also, the parents will eat the eggs right up if they get to them before you do. I get hatches all the time. The last one I got about 150 eggs on a sword leaf, snipped it off and stuck it in a net breeder box and had babies in about a week. Of those 150 eggs I had about 50 survive to sale-able size.
It's fun isn't it?! My current batch of babies are cherry barbs. I happened to catch a fry peeking out from some moss and promptly moved the parents out of that tank, and I have 30 viable younguns now.
Next: Flag fish!