water specific heat value?

Thought you'd know this because of your program.
Because of the drought I need to reduce water usage.  I have an immersion cooler now.
I also have a 1000G pond with koi.  I was thinking I could get another pump and use the koi water instead of tap water.
I "guessed" by adding the 48L of 373K (100C) of water heat to 4000L of 293K (20C) pond and came up with a 4.5C difference.  I think the fish would NOT like a 10F difference...

Is this correct?

You could switch to Pirahna  ;D

We have to pay for our "city" water, but we get it out of Lake Michigan and it is seemingly endless for now.

I'ver heard of guys using a huge 55+ Gal trashcan with a recirc pump from harbor frieght ($25ish) and some ice.  Then later they reuse the water for gardens, etc.

I have a friend with ridiculous amounts of rain water on hand for that type re-circulation.  Alas, you have no rain. 

With my IC, I use 20 gallons of tap (that I capture in a tub) to knock it down to ~110F (summer) and then switch to a cooler with 1 gallon of chilled water and ice and a pump.  Takes it down to 65F very quickly while recirculating the gallon and melted ice.  Total water is 21 gallons which I later use to water plants.  Basic sump pump is all you need.  Friends use pond pumps too.  Doesn't take much pressure.

After that the good things we must to undertake was to switch to a cooler with 1 gallon of chilled water and ice and a pump.


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Refrigerator Water Filter