Chicks and ducklings need food and water 24/7 when they are babies. My previous chicks I kept for six weeks on the enclosed porch and whenever I got up at night, 1:00 a.m., 3:00 a.m. & 6:00 a.m. to check on them and they were always eating and drinking!!! Sometimes I wondered if they ever slept. Babies need their nourishment to grow healthy, and plenty of water to keep them hydrated. I plan on keeping my now 6 weeks old chicks and ducklings fed and watered 24/7 until they are 12 weeks old. Then, food and water outside in the run.
Get a large waterer that holds 3 gallons...they won't knock that over. Rural King has a 3 gallon red/white plastic waterer that has a large enough drink bowl for the ducklings to get their bills and eyes in for cleansing, which they need. After graduating the babies from the feeders with holes in them for access, I changed to a 12 inch round plastic plant drain dish for their food. They don't knock it over and if any chicks poop in it, there is usually only one poop so I clean that out. For feeders, check out "feeders" on BYC to get lots of neat ideas you can make yourself.
As for the mess from the duck waterer...I put a black plastic bottom tray from a medium sized dog kennel, which has maybe 1 1/2 inch high sides, on the floor in the coop and set the waterer on it which keeps the splattering down immensely. I also use Equine Pellets in my coop which absorbs water, absorbs moisture in the poop, and breaks down to something that makes me think of damp looking wood shavings. It's easy to remove with a scoop, plus there is no smell at all in the coop. It's also a lot cleaner than using straw or hay which easily gets wet and can turn moldy. If you have chicks, they don't like wet feet.