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Thread: Shade balls
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Old 13th Aug 2015, 23:28
  #24 (permalink)  
Join Date: Jan 2009
Location: us
Posts: 93
ok, guys, but still - why black balls?
The black color is for UV protection of the balls and keep them from becoming brittle and breaking and then sinking.

The balls are trapped air which is a good insulation.
Apparently they have studied the application to the point that the insulating value of the trapped air more than offsets the evaporation from splashes on the black warmer surface of the balls.

Transferring the state of water to vapor removes 970 BTU per pound of water.
I would wonder if the water temperature of the reservoir will increase due to the lack of evaporation and black balls insulating.
At some point the water temperature gets too warm to dissolve enough OČ to support fish.

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