KRM is correct. As the grass becomes more dense and taller the water is correspondingly become clearer; both are closely related providing bottom digging "things" are not in the pond. Your jar test that resulted in a 3 day clearing showed this. Another thing to help the water stay clearer is stone, broken concrete, or riprap lining the shoreline. This minimizes resuspension of sediments due to wave action at the shoreline. Remember as the water becomes clearer the string algae(FA) and weeds will grow more abundantly and deeper. Dye helps slow this plant growth.
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