Nice set up! How big is the pond in the poly house? Do your ducks eat all the floating species in addition to the duckweed?
I scoop duckweed out of my aquariums when I get an infestation and dump it in the duck pond as a treat. Next year I will try growing it in a mini-pond outside as duck food. I agree with Chad, in an aquarium it is a horrible pest.
I did somd quick research and in an aquarium with fish it could be bad. A regular awurioum with just the plant not so bad, but outside in its natural setting seemed to be best
My ducks would like this. Is there othef plants that can go with it for ducks to eat?