They can breed - mixed clown pairs are quite common these days, and the occelaris and perculas are very similar in species. I believe the offspring will not be sterile (as I think some of the higher end designer clowns have an occelaris x percula parent), but perhaps someone else can chime in. But fry are very hard to raise - time consuming, expensive, and expect a lot of failure along the way. If you're definitely interested in raising the fry, then I'd recommend doing a fair amount of research first! Also, it can take clowns months to years of being in a tank before they start spawning, even if they are already a mated pair. Good luck!
