Try making your on food and feeding that.
Check out this link, great site with a lot of useful info,
Melevs Reef
Just go to the site map and click on it. Scroll down the page untill you see the heading food. It's on the right side of the page. Marc (Melev on this forum) goes into detail about making your own food. Very easy to follow the instrucitons, and your fish will love it
Cheers
Chris