High Kev kirk,
Plenty of information in our archives, not to mention icmag and rollitup, all with seemingly endless information pertaining to growing equipment.
Now that I got that out of the way, where to next, ah yes, tents that generate heat.
I own two tents, and I've been using tents for nearly seven years. I think I have some background to what I speak of, what experience does "a guy" have? Whatever...
Tents don't generate heat, they don't generate anything. That's right, a bit anal but accurate to the letter.
The only object in a grow tent that generates heat is the lamp, and if you use a CFL-type, it generates minimal heat, meaning high temps won't be an issue.
If you use a High Intensity Discharge (HID) lamp such as a Metal Halide (MH - Vegetation) or High Pressure Sodium (HPS - Flowering), the grow tent will become very warm/hot. In fact, without proper ventilation, the temperatures and humidity (an entirely different conversation) will raise to a level which will probably kill the plants, defo will have an effect on yield, as in low.
On the other end to the temperature spectrum, indoor plants shouldn't be exposed for any lengthy period of time to temperatures below 60F/15C. Why? Lengthy exposure to temps below 60F will affect the yield, if not kill the plants outright.
If you decide to read more, you will learn that the optimal temperatures for an indoor grow is 68-85F/20-30C, and the optimal Relative Humidity (RH) is between 45-60%.
These figures aren't set in stone, meaning that they should be used as a guide, let the plants tell you what they want "outside" these parameters.
Good luck and happy farming...
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