Humidity is getting high

I’m having problem with humidity at night My humidity is between 70 to 80 because it done got cool in Florida how can I lower my humidity

What are you growing in a tent, room or a closet? What equipment do you have such as exhaust fan, dehumidifier or osculating fans? The more information you give the better the growmies can help figure out a solution.

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You either need to move more air or add a heater to keep rh down at lights out.

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100% this.
Humidity spiking at night is normal, but knowing how to manage it, is the solution.

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I’ll third airflow. Airflow is your friend for a couple of reasons - temp management, RH management, and replenishment of CO2. Some growers will use a dehumidifier, but a dehumidifier can create another problem because it generates heat doing its thing. Airflow can help manage heat as well.

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Yeah, adding heat at night via a heater or dehumidifier makes keeping temps down the next day more difficult too. Its a tricky problem. If you can get the air in the room moved out then maybe you can reduce the levels. Don’t know if this could help, but leaving the home HVAC air handler in the “ON” position instead of the “AUTO” will help move the room air out and keep it more level with the whole house. I find the more difficult days for humidity is when the temps outside are such that the heater or air don’t run much.

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I have a separate tent for my dehumidifier, with A6 controlled IN/Out capability.
Adds 5 degrees and tames excess humidity. Both required in PNW un-heated garage.
HASHA. Exhausting air from grow tent can be controlled for increase garage temp or exhaust to attic and drop both lung and grow temps.
Didn’t want to run two tents , opposite hours, for more heat and less humidity.
Watering less helps lower RH, too.

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I’m in Florida, and the only way to lower humidity without adding more heat is to use AC. An air conditioning unit is a dehumidifier, but it doesn’t add extra heat to do it. My suggestion is to run the lights at night when the heat of the day is lower. Keeping lights out durning the day when your AC is non stop running will lower ambient temps more and keep the humidity lower when used in conjunction with your outtake an intake lines running. I keep the intake pipe on the floor by the crack under the bedroom door to suck in the coldest air I can

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As you can see. We have higher heat and humidity to deal with.

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Wish I had that problem… :disappointed:

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Middle of the day, lights out in tents.
Central AC set to 76°
Outside: 84° | 86% rH

3x3 veg


4x4 flower

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I have a 12x8 with a dehumidifier and an ac. Havent had to run the ac since friday because the temps dropped back down, but i supplement with 2 4 inch intakes ( i have them mounted over lights to help keep them cool, and then i have an 8 inch exhaust dumping into my veg room. I run my lights at night and im able to control humidity and heat. Im running 1800 watts in this room also.


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I just use the houes heat and air. My lung room stays at 70 73 rh in room is 45 during days and 50 to 60 at lights out. Dehumidifier put out too much heat for me.