I can tell you now that those coralife themometers are total crap. Not in the least bit accurate. I think this might be because they are calibrated to work in water. They suck at taking air temp readings or even substrate surface temps. The one I had is pretty close to accurate at around 75 degrees but it reads higher than real above that, and gets more inaccurate with every degree. Below 75 it reads low. Same thing. The lower the real temp goes, the more innaccurate it gets. Basically, it's off by as much as 8 degrees unless the real temp is around 75 degrees and there's no way that I can see to fix the calibration.

I hear they are all like this. Terribly inaccurate. Too bad you already ordered them. Seriously you're much better off using a home weather station, preferably one that can monitor multiple probes. Springfield makes some nice ones. They are accurate and affordable. They have many models to choose from. Here's one that monitors 3 probes. It's under $60 Springfield Instruments 91586 Wireless Multi-Zone Digital Weather Center - Weather Station