Most anemones would prefer finely chopped meaty foods. You shouldnt feed it large chunks of meat. It can hurt your anemone and it will not benifit from it. To keep your nems healthy and beautiful, give em' the right light requirments, quality water conditions and feed your nem apx 2-3 per week a diet that consists of finely chopped mysis, krill, brine, clams, etc.
One option is to get the frozen food already prepared (i.e. cubes or slabs). You can get a variety of flavors. I use a marine cuisine that has all the above mentioned ingredients. The food particle size is just right. I float 2 cubes in fresh RO water, rinse with tank water then suck it into a turkey baster and feed. They love it, it gives them easily digestable food and a wide variety of ingredients for nutrition.
Good luck and I hope this helps.