Confused about Temp measurements

[grisha]

Gents, I’m going nuts with temp reading between
Apex 76.8F
IceCap handheld white Gravimiter 74.5F
Hanna PH handheld temp showing 74.3
“Cheap watch battery lcd display wire in the display” -76
Glass floating thermometer 76 F

which piece should I believe?
Is there way calibrate apex probe?
Please help

 

[Gablami]

Average them all (except the apex) and use that. To calibrate, hit the settings icon next to the temp reading in apex fusion. Scroll to the bottom and hit calibrate.

Truth is, it really doesn’t matter that much whether it’s 75 or 76 degrees, or 74 for that matter. You probably could stand to raise the temp a few degrees, IMO, and then try to keep it stable. Good luck!

 

[Copingwithpods]

Best thing to do is just avarage them out and base everything off that, thermometers are as accurate as your faith in them. I avaraged out 6 to get my displays true temp

 

[grisha]

Maaan, I hope my wife doesn’t average out my kids temperature
Thank You for input
I just added another old Digital thermometer with wire in the tank. Reads 73.3 kind of brings down my average

 

[SonyaBAZ]

I found my apex temperature probe drifts quite frequently. Maybe it is time for a new one for me. I ended up buying calibration thermometer to calibrate everything. Otherwise I kept having my heaters and chiller fighting each other. With the apex drifting I have to check it every couple of weeks.

https://www.bulkreefsupply.com/traceable-long-stem-calibration-thermometer.html

 

[grisha]

Thank you
May end up trying this

 

[jda]

Mercury thermometer is the one that you trust. Calibrate the rest to it. Second would be a high quality laser temp gun (like not a Harbor Freight model), but this can get tricky and air and stuff can get read instead of water... best to shoot the water temp in the sump or other confined area... and they do not work really well reading off of glass.

I once heard that a man with two watches never knows what time it is... :) I guess that this is true with multiple temperature readers as well.

 

[grisha]

Yep, man with two watches ...