Thanks for the quick reponse. Unfortunately until the ice leaves I am unable to get that picture. I thought it may have been chara but not sure until now 9when I get a dig pic I will repost later) and yes I mis-label it as a plant knowingly it "bloomed" foam.
As to copper products - I stay away because of the alk. in the water and these are TROUT waters.

These waters typiclly are very clear and this chara is about the only thing in it. I never have the dirty turn-over as you see in some lakes. They are spring fed 9of course they take run-off from non-chemical treated lawns - only mowed and hauled away). The water is very hard.
These were built in 1992. Though this area is relatively low and full of artesians, I never had a water level/weed problem until in 1994 when a fprmer neighbor dug 2 1/4acre ponds within 400yds of me. Anyhow i just keep raking in the chara (if this it) from 15 feet out. Problem now is that the deep is being cluttered with it and concintrating all the fish in small pools - not good as I have 3 species in there.
Raking in the depths is out of the question. (that is even using the ol' cable and tractor method).

Thanks again.

Woody