IR Thermometer question

[GameCzar]

Since we will be keeping mostly nanotanks, I decided to go ahead and grab a decently rated, inexpensive IR thermometer.   The problem is that it's reading 5 degrees lower in one tank, and 4 in another.   Both of these tanks have digital thermometers, but lets be honest I have no idea if those are accurate either.

Should I get a cheaper mercury thermometer to try to get a true reading and see which might be accurate?

I love the idea of the point and shoot, especially for acclimating new fish but now I don't know what to believe! 😉

[Sarina]

The easiest way to tell if your IR thermometer is accurate is to open your mouth and point it at the back of your throat. Hold your breath while you do it so you don't breathe on the lens, but it should be between 97°f and 99°f. Sounds crude, but it's worked for me in the past 🤷🏻‍♀️ I've also checked it against digital meat thermometers, but not everyone has one of those kicking around. ±1°f isn't a big deal. Most fish can tolerate a few degrees of swing on the Fahrenheit scale and be totally fine.