What size tank do you have?
How much LR?
Tank mates?

Spotted (target) mandarins are smaller and a bit easier to wean onto frozen food. I would recommend that as a first attempt. ORA has captive bred, but I've hear those come in pretty small and are still hard to get to eat.

The best way to wean them onto frozen food is to keep them in an established tank by themselves. I believe Europhyllia has a thread where she did just that.

Also, keep a lid on it. I've lost two due to jumping after spending a lot of time getting them weaned over to frozen.