If I understand correctly, your lake is a mature BOW. IMHO The plankton should be there all on it's own if the water will support it. FWIW My first step would be a thorough water test and go from there. You may have PH, alkalinity, fertility, etc. issues that you will need to identify and correct if you are sure you have a problem at the very base of the food chain, i.e. plankton.

Just my 2 cents. Please keep us posted.

Bill D.

Last edited by Bill D.; 10/13/15 07:23 PM. Reason: Clarification
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