Re: NANFA-L-- Killer rain?

geoffrey kimber (gkimber2 at
Sun, 4 Sep 2005 11:26:02 -0400

Sorry - I wasn't clear about the O2 concentration (and I made a math
error)- The concentration in the atmosphere of oxygen is 21% which
works out to 210,000 parts per million, not 20,000 ppm (that's 2%).
At 14.7 psi (normal atmosphereic pressure at sealevel) and 20 degrees
centigrade, the maximum concentration of oxygen in water is 9.7 ppm

The point I was trying to make was that on the way down from the cloud
to your pond, the rain should become saturated with oxygen due to the
extreme gradient between the air (210,000 ppm) and the maximum
concentration of oxygen in water (9.7 ppm) so I doubt oxygen
deprivation is the cause of the fish deaths when it rains.

If you feel motivated enough, here is a page that has a calculator to
find the maximum oxygen concentration at a given air pressure and

Geoff Kimber
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