my pond is probably very similar to yours the water in mine is cryatal clear and i can easily go swimming and see every thing with goggles. i too had clpw in my pond and it is its highest in june and it slowly dies and is almost all gone by august but it always comes back every year at the same time and will die at the same time. it doesnt really move to areas that its not alreday there. it is really nothing to worry about plus it looks cool underwater and offers great cover for little fish if there are bass or crappie in your lake.
