I use a simple, cheap indoor/outdoor digital thermometer with the outdoor probe on a long (10' ?) cord. I personally just chuck the outdoor end into the pond from shore for a reading at 3' or so and then recheck at the surface, but one can easily drop it down from a small boat in measured increments for a detailed temp profile.


"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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