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Old 24-11-2007, 11:20 PM posted to rec.ponds.moderated
~ jan[_3_] ~ jan[_3_] is offline
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First recorded activity by GardenBanter: Apr 2007
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Default 15 inch deep enough for winte in Michigan?

On Sat, 24 Nov 2007 11:26:52 CST, Derek Broughton
wrote:

That goes against the principal that moving water doesn't freeze as fast
as still water, doesn't it? ~ jan


Still water will likely locally reach freezing point sooner than moving
water, but I was talking about supercooling, which is what "hyperchilling"
sounds like. If you have pure water (the purer the better) in a glass in
the freezer, you can probably get it to a few degrees below freezing - as
soon as you disturb it, or drop in a single grain of salt it will freeze
solid. Another simple example is to put a bottle of beer in a freezer.
You can take it out, see that it's still liquid, but the moment you pop the
cap it will freeze - it starts to crystallize around the released bubbles
of CO2.

Also, note that the common trick of preventing water from freezing in pipes
by leaving a faucet dripping has nothing to do with moving water not
freezing as fast as still water. That just involves bringing water from a
supply system at 10C fast enough that it never has time to freeze.

I just don't buy the idea that a goldfish can be "hyperchilled". Either
that means the water was sub-freezing - which shouldn't be possible in a
pond - or it means that some point above freezing is too cold for them, and
I have ample evidence that they survive well down to 0C (though I have,
from time to time, found little frozen bodies embedded in the ice - they
don't take that well!).


Check my reasoning.... So the reason slow flow movement in a pond keeps an
area liquid is, 1) because it isn't pure, and 2) it is keeping the temp
mixed? ~ jan
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Zone 7a, SE Washington State
Ponds: www.jjspond.us