Hi,
I have some of those heated plastic waterers. They are a one season item for us and a pain in the rear. I suggest a large rubber dog bowl. You can just knock the ice out of them and they do not break. (the black rubber ones) Not pretty but functional.
I do not have ducks so I do not know their water needs in the winter, we are fairly close to each other so our winters. I find the metal waterers with the sleeve over the kettle part on a heater works the best.
Just know nothing is perfect. Winter watering is a chore! and not fun for us.
Oh I tried the heat tape around the pan...failed,...