"John Bachman" wrote in message
...

In cold weather the diaphragm
gets stiff and cannot generate the pressure needed to get air down 36
inches or so (that should be about 1.5 psi).
================
I was told NOT to put the bubbler near the bottom where the warmer water is
in winter. It goes nearer the top to keep an opening in the ice. It should
not be deep enough to be roiling and mixing the colder and warmer layers.
--
KL....
Frugal ponding since 1995.
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
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