Best Thermometer?

Pazzoman · 2024-12-24T18:14:55-0500

Hey Everyone, I have 3 different thermometers for my tank. Was only using one, then decided to compare the 3.

I have a Dual Laser Infrared thermometer that I used to use to checking the basking temperatures for my bearded dragon.

Tank Temp: 73.2F pointed at water (literally touching the water)

https://a.co/d/449KJyy

Bought an aquaneat aquarium thermometer has a probe
Tank Temp: 77.5

https://a.co/d/dEkYYOg

Bought an on glass thermometer just for ease of temp viewing.
Tank Temp 76.1

https://a.co/d/c87JnDI

So trying to decide which one to follow, so I can adjust my heater accordingly. Unless there are real professional thermometers out there or a way to test for sure which ones are most accurate. If you have any you recommend and trust I’ll take a look.

Toby_Hook · 2024-12-24T22:25:06-0500

Infrared thermometers are not accurate for testing liquid surfaces. This should be stated in their literature somewhere. Though it is true for all infrared temperature gauges.
You'll get a more accurate reading testing the glass surface, though expect the glass to read 1-2*F cooler than the water. This is because the water is heating the glass to match the water temp, while the air is cooling the glass to match the room/air temp. Water is a better heat conductor than air, so it will be closer to the water temp, but not quite.

Based on the readings you listed for the other two, I would trust the accuracy of the aquaneat aquarium thermometer .

As outlined above, the glass temperature should be 1-2*F cooler than the water. And your stick on glass thermometer is reading 1-2*F cooler than the aquaneat aquarium thermometer.

All that said, the old school floating thermometers are generally the most reliably accurate. They are what I use. If you want something more practical, whether that the stick on or a digital, feel free to use any you like. But I suggest using the basic thermometer to test their accuracy.