Do you need to feed clean up crew?

I have just got a coral banded shrimp and have not been able to find out on The Internet what they eat. I have read they can eat small fish and hermit crabs, I don't have any small fish but have several hermits and would like to keep it that way. I have a lot of live rock will that be enough to keep it happy? I have a lot of Detroit that comes of my rock will he eat that? I also have rings of food for crabs and my brittle stars love will he eat those? I'm currently seeing if I can get my lionfish and coral banded shrimp to live together, they are both small at the moment and before I put the shrimp in well fed the lionfish and it had left it alone when I out it into tank but did try to eat it when it was in the bag getting used to the salt levels so fed the lion a bit more. Hopefully if the lion doesn't go hungry he will leave it alone!!