However, fiberglass window screening doesn't seem to have that problem,
being designed for possible contact.

Window screening does start to get brittle after 6-7 years. I replaced mine
last year after 7. I don't know if it would be harmful, but it wasn't
taking much to rip it. I have open-cell foam in the bio-filter after the
screening so it would not have gotten out to the pond anyway. Just thought
I'd mention it. ;o) ~ jan

See my ponds and filter design:
http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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