Bill D. - Basically yes, within a couple feet of the surface.

You can use a swimming pool thermometer, indoor/outdoor thermometer that is hard wired, one of those thermometers made for fishing, etc.

www.hoosierpondpros.com

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).