Reverend Budbreath
Red-eyed and mystified
I'm struggling with low temps and high humidity in my tent, which is out in a garage. With regard to the temps, I have a space heater out there on a thermostat setup, but it makes me really nervous having it out there unattended. And I'm afraid to take it to the higher of two heat settings in the close quarters of the tent, if only because I'm afraid it will really dry out the side of the fabric pot it's pointed at and maybe harm the plant in it.
The vicious circle is that if I crank up my exhaust fan a lot higher and/or have it on constantly to deal with the RH which is ranging from 50% to 64+% with the lights on (78% and higher for hours after watering!), then it will suck every bit of warmth out of there, resulting in decent RH levels but unacceptably cold temps. On the other hand, if I set my exhaust fan to be off most of the time (e.g. 30 minutes off/5 minutes on cycle), the temps get warmer but the RH flies up to 70%.
Then I had the idea of using big seedling heat mats, 48" x 20", two of which would almost cover the floor. Of course it's already been suggested that I use foam insulation sheet to get the plants (in 7-gal fabric pots) off the floor, and I was about to go get a sheet but then I wondered why not go one better and actually provide a bit of heat to the bottom root zone? Surely it would come up and warm nearly the whole of the soil, no? Unless I'm mistaken, when air temps are only moderately cold as they are in this case (60-66F), it's the roots and not the plant that really need to be warmer. If I were to do this, what would I set as the temp of a heat mat that fabric pots are sitting directly on top of? 72F?
I have a small dehumidifier (https://www.amazon.com/gp/product/B07WWFRG5R/ref=ppx_yo_dt_b_asin_title_o00_s01?ie=UTF8&psc=1) on the way that seems perfectly sized for a grow tent, and I hope it will solve both problems in one shot, but I don't know if it will be effective. Plus, I doubt the warmth from a dehumidifier would warm the bottom surfaces of pots sitting directly on the floor of a tent that is sitting on a cold concrete garage floor. So I think the mat idea might still be good.
Your thoughts...?
The vicious circle is that if I crank up my exhaust fan a lot higher and/or have it on constantly to deal with the RH which is ranging from 50% to 64+% with the lights on (78% and higher for hours after watering!), then it will suck every bit of warmth out of there, resulting in decent RH levels but unacceptably cold temps. On the other hand, if I set my exhaust fan to be off most of the time (e.g. 30 minutes off/5 minutes on cycle), the temps get warmer but the RH flies up to 70%.
Then I had the idea of using big seedling heat mats, 48" x 20", two of which would almost cover the floor. Of course it's already been suggested that I use foam insulation sheet to get the plants (in 7-gal fabric pots) off the floor, and I was about to go get a sheet but then I wondered why not go one better and actually provide a bit of heat to the bottom root zone? Surely it would come up and warm nearly the whole of the soil, no? Unless I'm mistaken, when air temps are only moderately cold as they are in this case (60-66F), it's the roots and not the plant that really need to be warmer. If I were to do this, what would I set as the temp of a heat mat that fabric pots are sitting directly on top of? 72F?
I have a small dehumidifier (https://www.amazon.com/gp/product/B07WWFRG5R/ref=ppx_yo_dt_b_asin_title_o00_s01?ie=UTF8&psc=1) on the way that seems perfectly sized for a grow tent, and I hope it will solve both problems in one shot, but I don't know if it will be effective. Plus, I doubt the warmth from a dehumidifier would warm the bottom surfaces of pots sitting directly on the floor of a tent that is sitting on a cold concrete garage floor. So I think the mat idea might still be good.
Your thoughts...?