Airflow, Temp & Humidity Q's - 4x4x7 grow tent

joeg235

Member
I was forced out of my closet (ok, asked to move) to the garage for flowering my plants (due to smell in the house. I bought a 4x4x7 grow tent and have a 400w HID HPS light there for flowering - this seems enough for the one plant I have - When I have more, I plan to add another light, if needed.

As soon as I moved to the garage I noticed the plant got Powdery Mildew (that I'm now treating).
I believe this is due to : fluctuation in temp (low 50 night to 70s day), higher RH in the garage and exposure to more "outside" influences (spores, etc).

I have added a small space heater and have a 12" oscillating fan in the box.
I have ordered a small passive dehumidifier as well.

I am wondering if I need to add airflow fans/filters to the box?

By the math (sq foot/5 = 22 fpm airflow) does not seem to indicate I need a fan and duct system. The box does have 3 duct ports (4" each, 2 on top and one at bottom left) and also 2 small screens at the bottom.

Since the box is not completely airtight I'm not really sure a fan and filter would be all that useful.

So...............................

I am looking for guidance here. I rent, so building an airtight room is out of the question; I have to work with what I have.

When I have up to 4 plants in there - will I need higher airflow than I have now?

Do I need a fan and filter - will it make a big difference with mold, etc?
thanks for any help you can give.
 
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