When you "put plastic over the top," do you have some kind of framework to
suspend it? Or does it just lay on the surface?

Hopefully Ingrid will give you the website, but yes, she has a frame work

I was thinking of floating bubble wrap on the pond. Any thoughts on that?

Better to suspend it, otherwise it blocks air/gas exchange. I do similar
with vinyl screening, which does help retain some heat, but better is when
snow falls, I get the igloo affect.

By the way, it's been so mild for the past week, right now my pond is ice
free. I hope it stays mild through Sunday; I may be going to the Packers
game in Green Bay. - Richard in Neenah

Have fun. ) ~ jan

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See my ponds thru the seasons and/or my filter design:
http://users.owt.com/jjspond/

~Keep 'em Defrosted~
Tri-Cities, WA Zone 7a
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