High temps in grow room

I have 1000w led and a 500 w led in a 4×2×5 tent . My humidity is 30 and my temp is 92 f . I’m 3 weeks into flower . Is this ok ? Theres lots of airflow. Cant take pic there sleeping. They look ok

I’d try and get it down into the 80’s if you can…


I hear high temp is good as long as you make sure it doesnt dry out or burn. I have led so no chance of burning and lots of airflow so no mold and I make sure to water. I’m in soil everything is organic.

You most definitely can burn your plants using LEDs, who told you that you couldn’t? @dbrn32 are you spreading rumors :joy::stuck_out_tongue_winking_eye: lol just kidding


Not me! Haha

@DUstincredible that’s too hot.

COPY/PASTE the below list into your forum post.

Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so; Or post
NA (non applicable)

  • What strain, Seed bank, or bag seed
  • Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF
  • Vessels: Pots, Grow beds, Buckets, Troths
  • PH of Water, Solution, runoff (if Applicable)
  • PPM/TDS or EC of nutrient solution if applicable
  • Indoor or Outdoor
  • Light system
  • Temps; Day, Night
  • Humidity; Day, Night
  • Ventilation system; Yes, No, Size
  • AC, Humidifier, De-humidifier,
  • Co2; Yes, No

Temps are temps… led or hps… don’t really matter…

Really tho…
Temps that high will be fine in soil… but dont think that your LEDs cant fry your plants…
I dont use LEDs … but even I know they can f&co $hit up if not used properly…
Watch your light heights…
More info on your set up is needed…


Could you be more specific about that?
How many inline fans?
What diameter?
How many CFM?
Do you have inlet and outlet fans, or just one?
What is the temperature of the surrounding room?

Regarding the lighting… perhaps you should turn off one of those lights. Also, you can raise them up to reduce the temperature at the canopy.


The LED panels CAN burn your plants!! Be careful!! LED burn does not look like nutrient burn there will be “bleach spots” on leaves and leaves will wither after about 2 weeks meaning it’s not easy to detect LED burn

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where r u measuring the temperature at and what is your ambient room temp.?

the proper place to put your thermometer is under the lights just above the plant tops.!

between 70 and 80 with lights on is ideal, some strains can handle higher and/or lower,
20-60% humidity is fine, 40-50% is ideal for flower.!
at 92 degrees Fahrenheit they r nearly cooking.!!
either your air ventilation and/or air circulation is not proper or u need a lower ambient air temp.!
my box draws and exhausts in a garage that is kept at 68-72 deg fer and 50% RH,
my box runs 76-80 with lights on, 40-43% RH, with lights off it gets 78-72 and 50-55%,
this is the best (most stable) growing conditions i have ever had.!! mwah hah hahhh.!! LOL

LED lights (especially blurples) actually cause light burn BEFORE any other light source.!!
i think this is due to the individual diodes producing different spectrums causing a concentration of a narrow spectrum to certain parts of the plant…???

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I have a 4×2×5 ten with 2 plants both in 4 gallons pots. I got the seeds off wish from China. I think its purple kush. Foods and soil is organic. I have a 4" fan with charcoal filter. 3 open holes for air intake . Also a fan running on th floor. . My temp during day is 91 f at night 78 f. In bud 4 1/2 weeks. There small buds but lots of them. Lots of airflow doesn’t need co2

That’s the second time you said that, but you still didn’t answer my questions above. I believe you probably do not have as much airflow as needed or your surrounding temperature needs to be reduced.

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We’ll see. I took the 500 out now temps 87 f.

ambient room temp is your biggest problem, u have a 13 deg swing, try getting the ‘night’ temp down to 65-70, then when your lights come on it will rise to 76-80 hopefully.!

with temps at 85+ they r probably gonna stay small and airy.

this is correct, getting the right amount of ventilation and circulation is the key.!!

what type and brand of fan and filter.?
a ‘booster’ fan will not be enough with a carbon filter on it,
u need a good centrifugal or mixed air flow inline fan.!

a 2x4x5 is 40 qu ft, with a filter u need 3-6 times that for good ventilation = 120 - 240 cfm,
this all depends on the type/brand of fan, size/brand of filter, amount and routing of ducting, ambient temp/RH, and amount of circulation in the tent.

Plants are gone. Apparently they where male and now I have a ton of seeds. Anyone tell me how to feminize my seeds ? Lol

This is my fan. 4" hose


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I got the room down to 82 day 75 night. A bit to late I think. Week 6. Small bud

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this is what they can look like at 40% RH and 76-80 day temps, 68-72 at night,
lots of air circulation and ventilation.!

if u want help with your temps u need to post way more info and pics.

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Turns out they where male plants lol got lots of seeds. Can you tell me how to feminize? Looked on u tube. Banana peels in soil in germination

In the process of setting up my 3 x 5 tent and am a novice but I had similar heating issues. Upon opening up another vent and putting in a variable speed controller for the 435 CFM exhaust I dropped the temps down from a high of 98 degrees to 72 - 77 degrees. I also had items blocking (garage grow) the one vent. Wasn’t actually blocking but was blocking any adequate air flow into the tent due to trying to hide the tent if I wanted to open the garage.

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Your plants most likely turned to hermaphrodites due to heat stress. They weren’t male but went hermy after suffering so much stress in their life lol

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