I feed mysis shrimp, in the frozen cube form. I cut it into smaller peices and put it into my tank frozen . My clown will then take a small chunk and feed it to the BTA. If your clowns dont feed your anemone, then you have to use a straw, turkey baster, syringe with a straw attatched, etc. to feed him. Suck up some of the mysis and place directly into his tentacles. he will grab the food and eat it. Look for signs of not eating as a possible downfall in health. Signs like an open, gapping mouth (should be tightlty closed at all times) or him grabbing the food then letting go, or not grabbing the food at all. I feed mine daily (when I feed the fish, the clown feeds the anemone), but that is probably in excess as they get their main sustenance from light and symbiotic zoxanthalae. Try feeding 3-4 times per week if he is under strong light, more often if he is under medium to low light.