BTW, the photo is of sago pondweed.
I'm confused, then. Was your reply below not referring to the embedded pic that started question 7?
Looking at that picture, the water is very clear, but that isn't Sago in the picture, now, is it?
Correct. That's not sago. In that picture there is a light algae bloom, with the groundwater coming in as a truer blue.
My ignorance of aquatic vegetation has got me hamstrung on this question! Crap! The overheat warning light in my brain just went into overdrive!