I have a 300 gallon preform. It get 4 hours sun. But its above ground
and when its 90 the water iis 80... How high can it go before the comets
and koi and turtles have a problem? I was told 85 or under is ok. But
what happens if it goes above 85? Is there any ideas to keep the temp
around 80-.? The bottom of the preform touches the ground. So I thought
it would be ok. The in pond pump is 200 watts and also a 20 watt light.
Does the pump put out heat also? Thank you

(DD DDD) wrote in news:22832-42A6685A-595@storefull-
3354.bay.webtv.net:

I have a 300 gallon preform. It get 4 hours sun. But its above ground
and when its 90 the water iis 80 [...snip...] The in pond pump is 200
watts and also a 20 watt light. Does the pump put out heat also?
Thank you


One way to keep the water cool is to set up a cascade, or better yet a
series of cascades. You pump the water from your pond into a much
smaller pond positioned higher than your main pond. Have some plants
growing in the upper pond that extend above the water line and cast a
shadow, for example irises. Allow the water from your upper pond to run
into the main pond. In this way the water in the upper pond will be in
the shadow of the plants and the water will cool from evaporation. At
low humidity this method is very effective, at high humidity less
effective.

And yes, the pump + lights yield 220 watts of heat, or 53
calories/second. That might be a small factor in keeping the water warm.
If your 300 gallons pond is mostly full, it holds 1000 liters of water.
If your pond were perfectly insulated and there was no heat loss from
evaporation (NOT realistic assumptions - just to give you an idea of the
heat flow) the heat from the pump and the light would warm up the water
by 5 deg C (8 deg F) in a 24 hour period. Of course your pond is not
insulated and there is heat loss from evaporation, so the actual warming
of the water by the pump and light are far less.

- Rich

On Tue, 7 Jun 2005 22:39:06 -0500, (DD DDD) wrote:

I have a 300 gallon preform. It get 4 hours sun. But its above ground
and when its 90 the water iis 80... How high can it go before the comets
and koi and turtles have a problem? I was told 85 or under is ok. But
what happens if it goes above 85? Is there any ideas to keep the temp
around 80-.? The bottom of the preform touches the ground. So I thought
it would be ok. The in pond pump is 200 watts and also a 20 watt light.
Does the pump put out heat also? Thank you

You might want to consider a beach umbrella on the really hot days. ~ jan

~Power to the Porg, Flow On!~