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Is airflow for temperature or humidity?

FarmerGreen

Member
Interested in getting opinions on this, I'm sure answers will vary.

I'm trying to dial in a micro grow in a bar fridge using 2x 100w led panels. The first grow wasn't epic
https://www.icmag.com/ic/showthread.php?t=355945

The fridge was still working and on a thermostat so the temp stayed a constant 71 degrees, which I thought would be good.
As the space was really quite small I was using a tiny 5v fan as an intake, creating positive pressure in the grow space.

Vegging seemed really good and vigorous, budding was light and fluffy- I put the light buds down to not enough lighting firepower, I was only using 100w at that stage. Plus I think it's not a true 100w, potentially as low as 50w.

The only thing I didn't measure was humidity. I have started growing again in the fridge and put a humidity sensor in the and it is all the way down at 35%. I've got a feeling I need to be up around 65%.

Should I just shut of my fan and have no airflow intake? Or do I keep it going and introduce a humidifier?
What does airflow actually do?
 

troutman

Seed Whore
Humidity below 45% causes very slow growth.
For flowering that isn't as big of an issue.
But for vegging you want it closer to 60%.
 

Douglas.Curtis

Autistic Diplomat in Training
Airflow is for prevention of mold, providing fresh air and for maintaining temperatures (cooling). In some cases it is used to remove high humidity.
Flower density is heavily tied to light intensity. You could have done everything just right, except having too low of light levels. It would have created fluffy cannabis. :) Congrats on finishing a micro grow. :)

Personally, I don't appreciate when my canopy temps exceed 70F. At this low of a temperature, I use low humidity to keep transpiration at high rates. I don't have exact numbers, but I prefer humidity at 30% and lower.

It's one of my secrets to growing trichome dense cannabis. ;)
 

FarmerGreen

Member
Airflow is for prevention of mold, providing fresh air and for maintaining temperatures (cooling). In some cases it is used to remove high humidity.
Flower density is heavily tied to light intensity. You could have done everything just right, except having too low of light levels. It would have created fluffy cannabis. :) Congrats on finishing a micro grow. :)

Personally, I don't appreciate when my canopy temps exceed 70F. At this low of a temperature, I use low humidity to keep transpiration at high rates. I don't have exact numbers, but I prefer humidity at 30% and lower.

It's one of my secrets to growing trichome dense cannabis. ;)

Is that lower humidity than most?
It was this vpd list that made me contemplate that maybe my grow room was to dry
https://www.icmag.com/ic/showthread.php?threadid=331510

If not, I'll just carry on as is. If so, how do I increase humidity without stopping airflow?
 
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