Cool! These are my first ducks too. I candled last night and saw little legs kicking. What breeds do you have? I got a mix of Khaki Campbells, Rouen, and Black East Indians.
It looks like I have 2 of the Black East Indians so far and 3 of the Rouens developing. The balance of the eggs were Khaki Campbell and all but two of those are developing. I need to weed out and count the good eggs to be sure of my numbers.