the large majority (over 80%) of wild caught mandarins that I have worked with will accept frozen foods. Dragonets are all very slow fish and need to be given the opportunity to eat. Confining a mandarin in a small area free of obstructions, and shooting some brine or small mysis shrimp towards the bottom usually does the trick. Once a mandarin becomes more accustom to frozen foods, it can compete for food in an aquarium if there arent enough pods to go around.