Might be mentioned already, but I recently picked up the Hanna CheckTemp and I had to adjust a couple of my inkbird controllers to match the hanna. If I ran both the apex and hanna I would calibrate both probes to the hanna!
HI98509 Checktemp 1 Digital Thermometer
Knowing the temperature of your reef tank is very important, and with the Hanna Checktemp HI98509 Digital Thermometer, you can accurately know your aquariums temperature within 0.5°F. Each Checktemp comes with a 3.3' silicone cable that has a stainless steel probe at the end that gives rapid...
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