Hi guys, new here (but not to growing). I was just researching propane heaters CO2 output and came accross this site. Found some useful info, and decided to stick to my thermostatically controled fan heater and electric blankets for winter use. Although a brief search through the forums showed me that no-one else has thought of (or at least shared) a brilliantly ellegant solution to a few problems. So I shall share :-
CO2 makes a huge difference to the health, size, and heat resistance of plants. And in an enclosed space, this can be a problem. I stumbled accross a nice solution awhile ago, which is homebrewing! Brew beer/wine in your growroom, near your circulation fans to spread it around, and far away from your vent fans so it doesn't get wasted. It is a perfect solution as plants 'breathe' CO2 in the day, and as temperatures are higher in the grow room in the day time, the yeast reacts faster, and more CO2 is produced. A quick search online will find you everything you need to get set up in homebrewing, and ofc as a bonus, you get cheap drink too! If you don't want/need the cheap booze, a brewing bucket/demijohn with yeast and sugar will do the job too. The next subject is heat, I mostly rely on electric blankets in winter, find one that has a 'night' setting, which is about 25c (80f ish i think) having these under your plants keeps the roots nice and warm and helps nutrient absorbtion, and most importantly, is about 20x more efficant than a fan heater, though i also have a fan heater with the thermostat set up to boost the heat on really cold night. Have a seperate electric blanket under the brewing stuff, as you will not want to be producing CO2 at night time.
Ok, I hope that helps, happy to answer any questions you may have.