How big is your tank? Are there any tank mates? Any particular purpose for breeding them? Do you know what you'll do with the fry once they hatch?
I'm not sure on how to condition them, but I have read that breeding them is more difficult than most other fishes.
When in doubt, Partial Water Change!
75 gallon ~AquaClear 110, Harlequin rasboras, Cherry barbs, Tiger barbs, Otos, Kuhlis, Rainbowshark.
10 gallon ~AquaClear 30, Guppies