There are several breeds of ducks. Each duck egg may hatch in different timeframes. The following steps will show you how to hatch eggs from the most common variety of duck, which is the Peking Duck, in an incubator.
Set the incubator to 99.5 degrees Fahrenheit and 55% humidity. Leave it on for a day or two to stabilize the temperature and humidity levels before placing the eggs inside. Set the ventilation by reading the incubator manufacturer's directions.
Select eggs that have been laid 1-3 days prior and are not misshapen or too big or too small. Inspect the eggs by shining a light through, or "candle," the eggs. If you see double yolks inside or notice any cracks, do not select these eggs.
Place the eggs inside a duck incubator insert tray and place the tray inside the incubator. Turn the eggs four-to-seven times each day.
Candle the egg after the sixth day of incubation. At this point, you should start to see spider-like veins developing around the egg. This is a good, fertile egg that is developing normally. Discard the bad eggs.
Remove the egss after 25 days from the egg tray and place them inside a special incubator-hatching basket. Candle the eggs again at this time to see if the egg is developing normally. Discard any eggs that have dead embryos.
Set the incubator to 99 degrees Fahrenheit and 65% humidity for hatching. Increase the humidity level to 80% and increase the ventilation so it is set at halfway as the eggs begin to hatch.
Lower the temperature gradually to 97 degrees Fahrenheit and the humidity to 70% when the ducks are mostly hatched. Ventilate the incubator to maximum capacity. Remove the ducklings when they are mostly dry.
You can order fertilized duck eggs online or from some local farms. When storing eggs before incubation, store with the small end facing downward at a 55 degree Fahrenheit temperature and at 75% relative humidity. Most breeds of duck hatch after 28 days, however Mallards hatch at 26.5 to 27 days and Runners hatch at 28.5 days. You may purchase a separate hatching machine to put the eggs in right before they hatch if you are incubating several batches of eggs at a time.
If after six days you see a light ring inside the egg when candling it, the egg has bacteria inside and will not hatch. If the egg is clear with no veins or you see a small dot inside it will not hatch. Discard these eggs. They could explode in an incubator and cause a huge mess.