Radiant heat and high temps

I’m new to growing and I’m looking to get some experience. I have the following:

Two 4" air intakes (passive system) outside room is 68-70 year round.
2 4" fans for circulation
6"x16" carbon scrubber in using a 6" to 8" reducer to have an 8" inline fan 442cfm
It’s lined with reflectix

I have a galaxyhydro 300w LED. I know it’s not putting out that much but, I’m had it to grow regular herbs.
I have an apollo 400w MH/HPS set up too but, it’s not in a cool tube.
Lastly, 4 CFL (23w to supposedly 100w) bulbs for seedlings

I have an issue when I using the HID light. The temps creep to about 79-81 in the shade. The radiant temps seem to be a little higher. Is there any way to control radiant temps and I was thinking about about adding another 4" inch air intake

Place a fan blowing across the top of the canopy in between the lights and the canopy , that should lower Temps at the canopy in at least bring them to room temperature so that it’s a constant , I always say , the more air the better … Without being to extreme…:smiling_imp:



Controlling heat sucks lol I don’t have decent fans like the ones with carbon filter and I have to crack the door to cabinet a bit and have a desk fan blowing hot air out and a fan on outside blowing in air Do it that way so I can dismantle cabinet in one minute if need be. I’ve always heard 85-87 good temp but also that certain strains more tolerant with heat but never could pinpoint how tolerant I ran mine at a nerve wracking 93 during August high heat not good for making tight nuggets but won’t kill it. I think 104 is when you get into plant death zone
I made a hill billy cooler with ice and a tote and a fan blowing cold air into box but with just freezer ice it didn’t last that long I usually grow with little cash flow though.

I currently have the 4" aimed between the light and canopy. I’m my area the the world, the outside temp was in the 40s so, I opened the windows and my in the room temp was at 61. That seemed to keep the box at 74 degrees in the shade and brought the radiant temp to 80. Will that be an acceptableevel to grow some good buds?

Hey @Rockchalk For Veg you will be totally fine at 80 degrees. Once you get into flower it will need to be a little lower. Temp and Humidity work in tandem. What is the humidity in your space. In veg you can be fairly high 40%-60%. Not recommended but it will tolerate it(the 60%). Once you get into flowering you want it to be lower somewhere around 40-45% max. Just something to consider moving forward.

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SativaStone right now, the humidity is at 38% and that because there is still some runoff in the tray. Since I’m using a 442 CFM fan, I wanted to explore the option of putting in another 4 inch intake so I would have 3 total. I run a 18/6 split with most of the time inthe evenings and early mornings when it’s cooler here. I just want to get the plant temp down since the box stays within range in the shaded areas.