they're one of the most difficult to breed, sexing them is very hard. they are an egg scatterer, the only think i could suggest is putting a create a couple of inch from the bottom of the tank to separate the eggs from the fish, with some green wool to attract the fish to lay their eggs there keep the tank clean, no gravel and leave them to it. It's the same method i used when i bred golden barbs much easier to breed (you could try them they're easier)