Is your new green bottom carpet just new Chara growth? Or is the green growing on top of the Chara? Is the water still clear? Can you collect some of the green and get a close clear picture of it. Maybe put some of it in water of a cool-whip lid for the picture?

If it is filamentous algae then the water from the stream likely contained lots of nitrogen to stimulate filamentous algae now growing on top of Chara.

How soon after you pumped stream water did the green develop?

Last edited by Bill Cody; 01/08/19 09:14 PM.

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