
Feeding
The ducklings are on chick starter (20-22% protein) for the first 2 weeks Red hen chick starter is great, then can switch to a starter/grower (15-16% protein) until they are 18 weeks old or switch right over to a regular (16% protein) layer feed at 3 weeks I use and recommend showbird breeder or xtra egg. Newborns I feed scrambled egg to for the first 2-3 days then change to the crumble
Please use non medicated or medicated chick starter not duck and goose or gamebird starter you can feed ducklings regular chick starter but since they require more niacin than chicks do to help with bone growth especially in their legs you will need to add human grade B3 to their food I use 500MG B3 Nicain tablets dissolved in water 1-2 tablets in a litre water container every other day until 3 months old this will do 1-5 ducks if you have more just add in another tablet or two they wont overdose they just expell what they dont use i their little bodies
You can also add raw uncooked oats to their feed working up to about a 25% oat/75% feed ratio. This can help avoid a condition called 'Angel Wing' which is caused by too much protein in a growing duckling's diet.
Treats such as lettuce, grass, herbs, weeds, and dandelion greens are all excellent sources of nutrients, but ducklings will only eat greens if they are fresh. I find that a handful of greens put into a small dish of water becomes a great way to amuse the ducklings and they gobble the greens up. You can also toss some peas into a tub of water. Anything green will be a huge hit with ducklings (and ducks!) Peas are also a good source of some added niacin, as are peanuts, peaches and sweet potatoes. Warm oatmeal and scrambled eggs are also a favorite treat. Please only feed treats after 3-4 weeks of age as tiny ducklings can choke easily on these
Do not feed potato peel or apple seeds
I have found ducklings to be more picky about treats than chicks, but anything green, mealworms, cooked spaghetti, watermelon, corn and halved grapes all seem to be favorites. I slowly introduce them to new foods, a little at a time, being sure that the starter feed makes up the majority of their diet.
Water
Ducks need to keep the membranes in their nostrils moist at all times, so as they grow they will need successively deeper water bowls so they can submerge their entire bill. A traditional mason jar, nipple or gravity chick waterers won't work well for ducklings. The mason jar design is too unstable and tips over too easily when you have rambunctious, clumsy ducklings and they quickly learn to empty the gravity and nipple waterers. Instead I simply use shallow flat bottom bowls or dishes and switch them out for larger ones as the ducklings grow.
I put their water dish in a oven tray to help with spillage as they love to play in it Ducklings can drown or get chilled if they sit in the water, so be sure to add some marbles or small stones to the water dish for the first few days or stick with a fairly shallow pan at first.
Room temperature water should always be available to them
Ducklings drink (and waste!) more than three times as much water as chicks, so be sure and check several times a day that they have clean fresh water.
I add a splash of apple cider vinegar or a tiny 5 cent dollop vegemite to the ducklings water after the first couple of days as a health booster.

Swimming
Swimming
Ducklings can swim at hatch, but they haven't yet developed the oil on their feathers unless they hatched under a mother duck, so until they are about a month old, swims should be short and supervised or the ducklings can actually get waterlogged and drown.
Drowning is the number one cause of fatalities in backyard ducklings, believe it or not. I let my ducklings swim around in a rubber dish tub for a few minutes at a time and then dry them off carefully with a towel before returning them to the brooder.
By the time they are a couple of weeks, old, ducklings can have access to a cake pan or clean paint tray in their brooder for water and will begin to take short bath in it, and by 5-6 weeks they will be able to swim on their own. I always make sure they have little stepping stones on the edge so they can get in and out easily.
Swim time is important because it helps to develop their leg muscles, and encourages preening which starts to distribute their oil glands.
Time Outdoors
By the time the ducklings are 3-5 weeks old, weather dependent, they can be outside for short periods of time on nice sunny days with adequate protection from predators, the sun and rain
Links
Follow the links to join two wonderful groups with lots of help and info and a place to have a friendly chat about all things ducks