Review on SunGrow Digital Thermometer - Accurate Tank Temperature Monitoring, 1.5x2.3 Inches, Black, Dual Degree Celsius & Fahrenheit Reading by Anthony Heinrichs

I have not tested the accuracy with another thermometer but there are very slight variations in water temperature (lights on/off). I would have given 5 stars if there wasn't one little thing that really bothers me. I can't get the suction cup that holds the reader to the outside of the glass to stick. It's okay, but it would be nice if he survived. The suction cup in the water that holds the probe works fine. First I tried wetting the suction cup but it didn't work!