Humidity in the night

Resurrecting an old thread because I am, too, battling humidity at night at the moment. I am hoping for, and open to, other suggestions on humidity management here…

Running up to 64% lights on, and 83% lights off. Here is the tent:

There are 3x small fans blowing on the canopy right now, and they are doing a pretty good job at moving shit around.

I have it, and another tent, exhausting together outside, like so:

Unfortunately, the humidity in my basement is around 60%, so the replacement air is not great.

I have tried putting the dehuey in the tent, but it heats up really fast. Much faster than can be evacuated. I am running air cooled hoods too. 1kW HPS.

So now, i am trying this:

The output of the dehumidifier is being partially blown into the tent. through a loosely attached 4" duct. It is working pretty well – air cooling is keeping up with the temp, and the humidity during my test went down to 52%.

Not that concerned with lights-on @64% because VPD is still a-OK, but lights off gotta do something NOW. Just entered week 6 and loaded PK, so things are gonna get dense and moldy right quick if I snooze…

Anybody else had good luck regulating tent humidity in rainforest climates? BC, PNW, UK etc? Even with the fan full tilt lights out, and ambient at 60%, in the tent it is 83…

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Some way of heating the tent during lights off?? Oil filled radiator or thermal tube??

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Well, the tent at lights out is at 19-20C, and 24-25 typically with lights on. I have not tired dehuey with lights off inside the tent yet though, that would heat the tent too.

Any harm in having daytime and nighttime temps the same? I have always tried to keep 24C/20C or thereabouts

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I work in f :rofl: I often hit high 80s during lights on with no Ill effects. Normally it drops to low 70s lights off. I’m running auto pots so coco constantly wet and humidity does get high. As long as plenty airflow on lower section of the plants you should be fine.

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TRAITOR! SHAME! :joy:

Thanks @Esrgood4u OK i’ll stop worrying. Airflow across the canopy is great, i know that much. Will adjust the setpoint to 29C (85F) for air cooling (that should get me an extra few % RH on the VPD), and heat the tent at night with the dehuey on a 1 hr cycle.

Will report back tomorrow

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Airflow below the canopy will help a lot. Just make sure the warm air is constantly moving. Good luck @HappyHemper :+1:

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Added a fan. Moved an extra one to below the canopy:

Fan 1:

Fan 2:

Fan 3:

Fan 4:

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Below the canopy has nothing on it :joy: you obviously been on a trimming mission. I think you’ll be fine as long as the air is moving. I’ve done full grows with nothing stripped and humidity constantly high without bud rot.

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LOL yep, paranoid about humidity. Paranoid to lose any of this crop. I fucked the last one up proper, so Mrs. ran out. $350 to get her through the next 3 weeks till I chop and quick-dry some. I would much rather have spent that $350 on something for the garden… Like framing it in and/or getting an AC unit. Already have everything else for CO2…

Such is life though. Thanks again, i’ll sleep better now :wink:

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VPD Chart :chart_with_upwards_trend:

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If your that stressed about humidity fill a couple of trays with cat litter and place it in the grow area.it will suck the moisture out of the air. Cheap easy fix that “should” help it drop

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I have set the dehuey inside the tent too for the night hours. It is on a timer two hours on, four hours off, and internally set to about 55%.

When I spot checked at night, the humidity was between 48 and 64%, leaps better than the 80 I was getting before. I sweat the buds frosted more overnight too, but then again this is end of week 6…

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