One of my ponds looked a lot like yours. A couple of months ago I built a floating island that is about 24 square ft. I found sedges and spiral grass a Lowes. I don't know if it really did anything, but over the past several weeks nearly all of the top water blue green algae has disappeared.
I not a home this week, otherwise I'd post some photos. Maybe next week.
P.S. The island is in a 1/3 acre Pond.
Last edited by catmandoo; 09/11/15 07:54 AM. Reason: Add P.S.
