Well, I actually have two separate feeding issues.
In one tank I have a smaller blue dot puffer who I am slowing getting to eat frozen foods. I am feeding frozen mysis, rod's food, squid, and gamma. in addition, i threw some small blue legged hermits in there, which he actually went after. i see him picking at the live rock all day, but he is still somewhat skittish about going after the frozen food. he does alot of eating and then spitting out. i tried some ghost shrimp and he got excited and chased them, but had a difficult time catching them (i think he finally did get one or two)
In the other tank i have a dwarf lion who will not touch frozen food. He did however devour any ghost shrimp I put in there.
Both tanks have attached refugiums. My plan was to get a good quantity of these white shrimp and put them in the refugium and harvest them for the tank. Nutrition would be another factor i have to consider.