Temprature?? What to trust?

[GatorReef]

So things started to look a bit off, but the APEX was showing that everything was fine. Put my hand in the water and it felt a bit cold. I try to keep things between 76.8 to 78.1 also know that they are all part of the same water/filter system

Device 1 78.0 - Sump - APEX
Device 2 76.4 - 55gal - cheap aquarium Thermometer
Device 3 75.5 - 60gal - cheap aquarium Thermometer
Device 4 75.2 - 60gal - Seneye

 

[Crabs McJones]

So things started to look a bit off, but the APEX was showing that everything was fine. Put my hand in the water and it felt a bit cold. I try to keep things between 76.8 to 78.1 also know that they are all part of the same water/filter system

Device 1 78.0 - Sump - APEX
Device 2 76.4 - 55gal - cheap aquarium Thermometer
Device 3 75.5 - 60gal - cheap aquarium Thermometer
Device 4 75.2 - 60gal - Seneye

I asked the same thing, how do you know what to trust. Another user showed me this video. Basically you put your thermometer in a known temperature, in this example 32 degrees since water freezes at 32 degrees. And you can do the math at how far off your thermostat is, and then use that difference to calibrate

 

[GatorReef]

I asked the same thing, how do you know what to trust. Another user showed me this video. Basically you put your thermometer in a known temperature, in this example 32 degrees since water freezes at 32 degrees. And you can do the math at how far off your thermostat is, and then use that difference to calibrate

Thanks, you know what I'll be doing tomorrow