More info on Chara from Kelly Duffie.
"" The "weed" is actually a form of algae known as Chara, muskweed or by its well-deserved nickname - skunkweed.
You can read more details about this infamous pest HERE:
http://aquaplant.tamu.edu/plant-identification/alphabetical-index/muskgrass/Chara is a tough critter to tame. Physical removal, when possible, followed by judicious treatments of CUTRINE PLUS Granular seems to work fairly well - up until the time that calcium deposits begin to form on the Chara as the season advances.
Judging by the density and maturity of the Chara in your photos, it may be beyond a successful chemical treatment this season.
Water-hardness (high), excessive water clarity and nutrients are likely major contributors for its abundance."" end quote.
