Can’t get humidity down with 2 dehumidifiers

!!This is my first grow ever!!

Gorilla glue auto flower from ilgm
Soil- happy frog
Nutes- fox farms trio
Tent- Mars hydro 4x4
Light-Mars hydro tsw2000
2 dehumidifiers
2 clip fans
In line fan running on max
Day 43 of grow
2 weeks since flowering started

I have my grow tent set up in a shed outside in Virginia, I can not get the humidity down below 70-80 rh, I have tried increasing circulation and decreasing circulation (opening more vents and turning all the fans on high) and it doesn’t seem to make a difference. I feel like this will cause problems like mold once the flowers start packing on weight, and tips or ideas???

What RH meter are you using? Cheap ones can be off so I’ve always used at last 2 different types. But you know you’ll have to get some dry cool air in the tent. Lot of heat coming off those dehumidifiers. I think the weather in Va. calls for lots of rain in the next few days? I could only recommend a portable a/c. At least until the weather turns cool there. I would think that you might have 2 weeks till the cool fronts start. Plants looking happy, I think the fall weather is gonna be your friend in this grow


Have you tried leaving the dehumidifiers outside of the tent and just in the shed? How is your ventilation? Is it pulling from the shed or outside?

@stillincloset i agree the temp is supposed to drop after today, I have been fighting the temp the entire grow so far, the humidity is just becoming a problem, I also have 2 different humidity gauges in the tent and a they can sometimes differ pretty drastically from each other

@Maddthumb i haven’t tried the dehumidifiers outside of the tent, the shed isn’t sealed worth sh*t so It’s getting a lot of air from outside coming in, the tent is getting air from the vents at the bottom of the tent with in-line fan pushing air out of the shed

Check you hr metter if the tent is open and fan running you hr need to get down a least 10%

I would try different things. Either put dehumidifiers outside the tent. Or add a seperate duct for intake of outside air. You probably dont need a fan on the duct just let your exaust pull the air in passive. For sure the shed is your problem holding all the humidity.

Ac unit

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I’d be shocked if you were over 70% in Va. and that humidity is going to come down fast.
Weather has been holding me back from flipping because of the rain this year. I can shape for a long time but come on…rain rain go away…btw: Northern Lights, 5 gal., canna bio-terra/nurients, groplanner O-150 (checkout migro), cheap 2.5’ x 2.5’ x 5’ tent, 3 usb fans, Infinity 4" exhaust fan, and 1 yard stick…