Exhaust Fan Question - First Time Grower

Hi all. I started growing three autos (Girl Scout Cookies, Gorilla Glue, Bruce Banner - the “Super Mix”). As a complete beginner, I was hoping to keep things as simple as possible, so I purchased the medium size grow kit from A Pot For Pot. I started them in jiffy pellets per the kit instructions and had them on the window sill where they were stretching like crazy. So I purchased a humidity dome with a T5 light, moved the seedlings into solo cups (still in the jiffy pellet but with the fabric cut off and the rest of the cup filled with soil), and they seemed much, much happier.

They were then transplanted into 5 gallon pots (with the “super soil” included with the Pot for Pot kit) and placed in an AC Infinity 2x4 tent - I bought the kit that comes with tent, LED light, fans, carbon filter, etc. I had initially set up my exhaust fan to always run at level 1, and then kick up to level 3 if a temperature or humidity trigger is met. However, constantly running the exhaust fan on the lowest setting brings the humidity down to about 40%, which is the ambient humidity in my basement at the moment. So, I now have the exhaust fan off until a trigger is met. My triggers are 82 degrees and 65% RH.

The result is that the temperature is consistently maintained at 79-80 degrees, and the RH is always between 63-66%. So, my question for the experts here is…

Is it bad that the exhaust fan only kicks on for a second or two every few minutes to adjust the RH down? Should it be running constantly (or more frequently) for air flow? I have a circulating fan running 24/7 at level 3, and one of the tent’s bottom vents is open.

To my untrained eye, they appear to be doing OK - each plant has some yellow spots on the first set of leaves, but the newer growth looks better. Those yellow spots appeared after misting the plants early on, I wonder if maybe the water droplets magnified the light and caused a bit of burning? The GSC does seem to have a bit of yellowing at the leaf edges and tips. I’ve been watering with my well water, which I tested today - PH is high, around 7.5. I’ve ordered a PH control kit which arrives tomorrow.

Thanks, I’ve been lurking around here for a while, and this forum has been extremely helpful in getting a first timer off the ground. Already looking forward to the next round - photoperiod Zkittles from ILGM in FFHF/FFOF!

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I run my fan 24/7 just to keep a fresh air exchange if your plants look good I don’t see a problem I use a humidifier in my tent when I need to raise the RH

I run my oscillating fan 24x7, above canopy and below or into lighting crown. The AC-I-C 67 set for cycling from off works for lights off. Temp is low during lights off and exhausting T6 fan set at minimum cycle (3/7, on/off, Zero/Three speed setting, respectively). Input T6 input fan set similar for support/back-up.

Thanks fellas - lotta helpful Daves around here!

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