The man is asking for input.
So there are things to consider.
Is this lake a natural lake? Is it a reservoir? Does it get runoff from farmland?
Most growers would not want to be applying pesticides and or other contaminants that may be carcinogens when the Cannabis plant uptakes.
Cannabis is famous for taking up heavy metals, chemicals and radiation. Hemp has been used to detoxify soil.
So in my medical growing realm I advocate not using dangerous to one's health soil, water and other chemicals.
I say all this as more input for
@victoryou That's why they have asked question I am sure.