Another thing, I'm spending roughly $150 a year on Whitecap. A $6k gizmo has a long payback--40 years. it's not just the duckweed/water meal, but the leaves. Not sure why, but willows dump leaves every day it seams--makes for a mess.
I think with duckweed control, i wouldn't be collecting a lot of material, but the process of skimming weekly would keep a nice looking pond. It's almost july and I've not yet collected a compost bin of duckweed/leaves.
Prior to chemical treatment, I could skim a compost bin almost daily.
I'm surprised the water level hasn't been affected all that much--I thought duckweed might keep water from evaporating.
Bennie
LMB, HBG, YP, CC, FHM, located SE Michigan
1/3 acre 8-9' deep, aerated 24/7 1/4 hp rocking piston