I finally gave up and ordered an UV clarifier. The pond will be covered
with an arbor someday but for now it gets too much sun. The algae bloom
has been heavy for 5 weeks plus.
The very day the UV arrived the algae was gone. Crystal clear to the 3'
bottom. I installed it anyway. The algae gods are such smart alecks.
They must be more like algae pixies rather than gods.
Mark B.