And the recommendation by e-mail was:

FORMALIN since the pond contains many plants. Salt would be out.

1 oz. treats 500g and costs around $9.00 for a 16 oz. bottle so it's
economical.

Thanks for the reply ;-)
--
ZB....
Frugal ponding since 1995.
rec.ponder since late 1996.
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
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