I quarantine my feeders (2 weeks) and feed/stuff them first with pellets (pellets that my dats dont like but high in nutrients that they need) before giving it to my dats
Mine feed on Futian freeze dried shrimp and Hikari sticks. They straight murder the stuff. Pellet training all stock is the way to go. They don't eat, they starve.......then eventually eat and start begging for it.