Dr Engelbert Buxbaum wrote:
Elaine T wrote:



Come to think of it, I wonder if that's why people report such variable
results with formalin-based fish medications. Old bottles would be of
limited use. I had no luck at all this winter trying to cure ich with a
2-year old bottle of Quick Cure. Hmmm...I'm off to put my formalin in
the refrigerator - cold slows the breakdown.


No, the conversion of formaldehyde (or methanal, as the systematic name
is) into paraformaldehyde (the polymere you were talking of) is
accelerated at low temperature. Formalin is best kept at room
temperature, protected from light and in an air-tight bottle (not only
to protect the formalin from air, but also to keep the formaldehyde in
the bottle, as it stinks badly, is a potent allergene and quite toxic).

Thanks. That shows how inaccurate biology lab lore can become. The
(admittedly rather odd) lab where I used freshly depolymerized
paraformaldehyde kept it in cold overnight.

--
Elaine T __
http://eethomp.com/fish.html '__
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