Mysis is good. Also, ArtiPods are good if the fish are small. Spirulina Brine shrimp (not regular brine).
Something most people overlook or just don't know:
Clown fish are actually omnivores, NOT carnivores. This means that they should not ONLY be offered meaty foods, but many will not just take vegetation like a tang or anglefish will. A good solution to this problem is spirulina brine and EMERALD ENTREE which has both vegetation and meat. Vitamins is always a good thing, but don't use too much.