Sorry missed this one.
I believe Aquathol would be the recommended chemical to spray with. How much Naiad do you have? If it's spotty, then spraying might be the easiest. GC are less selective, and may eat any good vegetation you might have.
If the Naiad is slowing down like everything else, then Aquathol might not work as well as in the summer, when it's actively growing. Somebody else will have to answer that.
Dye would help control any submergent weeds, but it would also inhibit any algae bloom that your BOW needs. It's a catch 22. If you have 10' of visibility, then I would control the Naiad, then fertilize in the spring when it warms up. That would reduce visibility and help control new weeds.
Here's a link that might help
