If you see him wearning a bandana and carrying a canteen...it is probably too hot. (These are signs I have seen in the past.)
Temp guns are nifty...so are max/min thermometers...both good and used for different things. Buy one of each.
The temps guns can tell you the temperature of any spot in the enclosure within seconds. Pretty cool if you are perioically SPOT CHECKING the temperatures.
If you want to MONITOR the temperatures (completely different thing) then you would prefer a max/min thermometer.
I prefer to monitor the temperatures. There is no way to really monitor your highs and lows with a temp gun...unless you temp gun the same spots every few seconds for a twenty-four hour period. And that's a lot of temp gunning!
Big Apple has a very decent dual-probe max/min thermometer. (I also like their dual-probe thermometer/hygrometer unit. Cool stuff.)
Buy a max/min thermometer. Monitor the temperature fluctuations for 72 hours. Adjust as necessary. Leave on vacation. Feel safe.
Chris
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mean people suck