Ihe close up pictures were much more helpful. If the water is hard and has moderate to high alkalinity then it is Chara. If you have soft low alkalinity water then it is likely Nitella. Both are plant like 'stemy' forms of algae with no true roots. It looks a lot like Chara. They are early primary invaders of ponds; often the first to arrive as submerged vegetation.

Last edited by Bill Cody; 05/12/19 07:04 PM.
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