You have two sizes, i kept a bucket of water for mama(too tall for a duckling to get too) and feed they can share the same shallow container or add two.. or a larger size for mama duck just depends on what you choose to do.
Same as the mum, feed and water.. just in containers in which they can reach.. i actually just use a clay pot saucer for feed and then stick one under the chick waterer to sturdy it more.
I'd look for a flock raiser, that is what i have mine on.. it's non medicated and for poultry a day and up. If she is locked in with her baby there is no foraging so any extra nutrients are inaccessible. For young, i use a mason jar chick waterer that is enough while they are little then before...