quite tricky to breed apparently, the main issue being that their eggs are sensitive to UV light meaning they need a dark tank with lots of plant cover. Unlikely to be successful to get them to do so in any sort of community set-up or display tank.
There was a good tetra breeding article in PFK September, worth a read if you can get hold of it. Your local maidenhead may keep old copies. The manager of mine offers me to borrow old copies for research
Maidenhead = Maidenhead Aquatics, large chain aquatics retailer, branches all over the country
PFK = Practical Fish Keeping, specialist interest magazine.