The secret to good tent control is a filtered inlet fan as well as a ( for smell mostly) a filtered outlet fan. The inlet fan can be in a box with the duct from the fan going through the side of the box into the tent to be distributed. Tape the box shut and sealed with the hose going out the side also sealed, and tape a good house filter on a side of the box. The box has to be sealed because inside is a lot of negative pressure to suck air through the filter. I use 10” x 20” 3M 1900 filters, which collect a lot of dust and dawg hairs, and most importantly prevent spider mites and maybe mold. This was the change that really improved my plants.
The exit fan and inlet fan run continuously, set to achieve desired flow of lung room air into the tent, and warm moist air out of the room. Differential speeds between the inlet and outlet fan determine the tent pressure relative to the lung room. I like just a touch of positive pressure, enough to slightly puff out the tent, so there is no dust or mites getting sucked through the zipper leaks.
My 6” AC Infinity manual control inlet fan runs at setting #3, the dual filtered 6” outlet fans are at 5-6. Those go through a 8” wall fan that is barely running. Don’t want too much air noise on the outside exit. Running the fans at a constant setting is best. Forget trying to control humidity and temps with a controller. Get a little 3 sensor remote temp/ humidity unit and locate the sensors to read different locations in the tent. Dial in the fan flows and lung room conditions to make the inside sensors read what you want. The location of the sensors in various places in the tent will Vary in temp and humidity a lot, depending if they are at soil height, midway up the plants, or at the tops where the light heat is and moisture from the leaves.
Growing during the cold dry North American winters makes life a lot easier. Adding humidity is easier than taking it out, which usually also adds heat. Fighting the ambient summer weather is a lot of work and expense and electricity and noise.
That is my formula for good environmental control, simple and stable. Tweaking the lung room with a space heater, humidifier, and hanging out in here with the dawg for CO2 generation, works.
See the grow room section for a good tent SWICK water system for automated watering for bags of living soil.
The exit fan and inlet fan run continuously, set to achieve desired flow of lung room air into the tent, and warm moist air out of the room. Differential speeds between the inlet and outlet fan determine the tent pressure relative to the lung room. I like just a touch of positive pressure, enough to slightly puff out the tent, so there is no dust or mites getting sucked through the zipper leaks.
My 6” AC Infinity manual control inlet fan runs at setting #3, the dual filtered 6” outlet fans are at 5-6. Those go through a 8” wall fan that is barely running. Don’t want too much air noise on the outside exit. Running the fans at a constant setting is best. Forget trying to control humidity and temps with a controller. Get a little 3 sensor remote temp/ humidity unit and locate the sensors to read different locations in the tent. Dial in the fan flows and lung room conditions to make the inside sensors read what you want. The location of the sensors in various places in the tent will Vary in temp and humidity a lot, depending if they are at soil height, midway up the plants, or at the tops where the light heat is and moisture from the leaves.
Growing during the cold dry North American winters makes life a lot easier. Adding humidity is easier than taking it out, which usually also adds heat. Fighting the ambient summer weather is a lot of work and expense and electricity and noise.
That is my formula for good environmental control, simple and stable. Tweaking the lung room with a space heater, humidifier, and hanging out in here with the dawg for CO2 generation, works.
See the grow room section for a good tent SWICK water system for automated watering for bags of living soil.
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