Aphanizomenon has several different species and each tends to have its own favorite water conditions to form blooms. As a group it can thrive in low nitrogen conditions. Amount of phosphorus tends to be the main stimulus when blooms form. It has been reported in low and high nutrient water. I think you should see significant reduction in density when water drops around or below 60F. Again, somewhat species specific regarding preferred temperature.

About the only way to determine the specie is look at it at high magnification and know what you are doing to recognize the specific characteristics to identify the species.

Last edited by Bill Cody; 09/17/19 08:31 PM.

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