I have a feeling it gets to cold in the tent. I wrote a python program to read the temperature inside the tent, compare it with the lowest previously recorded value and overwrite if current value is less than the previous value. 

At some point I'm going to expand on this and use a csv file with matplotlib to create graphs of this data. This should get me started and give me the information I need.

I'm using a cronjob to automate the task. Every 20 minutes it's running this check.

*/20 * * * * python /home/pi/Documents/code/grow_lib/lowest_temp.py

Current lowest temp recorded is 64.94 F. It has been going for a couple of hours.