Same here, I have used the Purina Duck crumbles for babies until they are fully feathered and then switched over to the Purina Duck Pellets for the remainder.
For reference, I have 8 ducks in total:
2 Silver Appleyards (M&F)
1 Muscovy (F)
1 Blue Swedish (F)
1 Welsh Harlequin (F)
3...