On Mon, 19 Feb 2007 19:49:27 GMT, ~ jan
wrote:

On Mon, 19 Feb 2007 13:19:36 +0000, Gill Passman
wrote:

Just one other question on the water movement/aeration - if you did this
(ie. aerated from the bottom rather than a fountain on top) in a smaller
pond, such as most of us have/will have, wouldn't it have the effect of
chilling all the water and losing the low level haven that
fish/creatures use to over-winter?
Gill

It's been found that in shallow ponds, under 4-5 feet there isn't much
stratification going on. I know in my 3 footers, it would be pretty darn
cold.... thus why I chose to keep a heater in it and use as needed. ~ jan


This is true. Less water to turn over so differences usually are
less. I know sopme of my wifes preforms are the same temps from top
to bottom and IIRC the deepest preform is about 20" The preforms that
are inground" however stay a bit warmer overall (up to a certain
point) than those water features of comparable depth that set totally
out of the ground (half whiskey barrels, Stock tanks etc)

I stil need to check that 100 watt heater setup out. Its still hard
to belive its gonna raise up the water temp in extreme cold weather
and a large volume of water......

I knew a fellow who used to pull water up and circulate it in winter
to keep his pond from freezing. It was large enough to have a l;arge
impact from ground temps on the bottom which were above freezing. His
pond was the only one that was around that never had any ice on it.
This was when I lived a bit further north. Its the same principal that
they use in the freshwater boat slips to keep ice from freezing and
damaging the hulls..........they submerge a propeller type device to
pull up warmer water from the depths and mix it in and around the
surface water..... I guess just 1 deg or so is sufficient to make a
difference

I still can not get over a 100 watt heater though! ;-)


-------
I forgot more about ponds and koi than I'll ever know!