To Duckweed or not to Duckweed

Pond is a little bare this year due to the cooler weather. The Water
Hyacinth are surviving, but not flourishing. So I wanted to introduce some
other quick growing cover to help with the Algae and provide shade, as well
as a nosh for the GF.

I've read good and bad about Duckweed. I've got a 500 gal pond with 9 GF,
will Duckweed take over or will the GF ravage it? Should I grow it in a tub
and add as required? Do I need to coral it in one area to prevent
competition with the Lillies and WH?

Advice appreciated. I'm in southern Ontario BTW.