Temps too high in tent

Hey All, I have been struggling to keep my temps down in my tent. They hover at 83f-84f.

I am running a Spider Farmer SF4000 in a 4x3 tent. AC infinity 6” fan. Both side vents are open. The temps on the basement where the tent lives are in the mid 60s.

Any advice??
How bad is 84f?

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I’m doing fine with it but I’m running co2.

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Put ice in a bowl and direct your fan air to pass over it. Or you can put the ice bowl in front of your intake vents inside the tent. It helps

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@Chicojackson you can run up to 90f with c02 without any harm as long as humidity is good and your c02 ppm is above atmospheric average of 412 ppm. Between 80-90f you’d want 500-600 ppm c02. What’s your humidity at right now?

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@Chicojackson nvm. I just saw you have 50% humidity. You need to bring that up for higher temperature and c02. Between 75-80% humidity is needed at those temps with c02.

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@DojaGrow Get another 6" fan and suck air into the tent. If the room is mid-60’s, you need to suck that in! And crank the flow up on them. What speed is your 6" running at?

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@DojaGrow Have one oscillating fan dedicated to blow on the light since you can’t mount driver outside of the tent.

Do you have just one exhaust/intake fan? If you only have one fan use it as an exhaust fan and do the passive intake like you have. Just have to add another oscillating fan to circulate air around the plants under the light too.

If you have two intake/exhaust fans that are adjustable using a positive pressure system helps a lot when you have low temps outside and high temps inside. Set exhaust fan to run on low up top and intake fan to run on high at the bottom. The forced cool air coming in will help with air circulation and force the warm air up top by the light and exhaust fan.

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@MDBuds I normally run it at 65 but I will take it up to 75 and take the advice. Improvement is what I’m here for.

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Maybe switch out and run lights at night when it is colder and off during the day when temps are usually warmer

I leave my tent open when the lights are on. I’m happy with my results. I’m sure there’s some technical reason I’m wrong but I like it.

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I ended up buying one of those powerful 6” desk fans, and sitting if right in front of the intake window. Temps have leveled out at aroun 76-78 when lights are on, and 65 when off.

Thanks for the info! I was always in the mindset that negative pressure was best. Now I know!

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84 isn’t.to Bad.at.all…u may have to.upgrade.ur exssust to.bigger.one.

Turn down to 90% ok​:v::v::v::pray:

84 isn’t bad. You just want your humidity to be in the right range
This vpd chart helps if you haven’t seen it.


If you’re worried about the heat there are many ways to cool it down. But I think you said it was in a 60f basement. You could always just put a fan by a bottom vent and fan cold air in. Play around with different fan speeds, humidities, and even the direction the fans are blowing. Keep tinkering until you find a vpd that works for your environment. Just my thoughts.
Happy growing :fire:

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Add a fan blowing directly on the light and add an intake fan to cycle in that cool basement air. No brainer if your basement is in the 60s. First move is to add intake.

My plants really don’t even look happy till it gets up to upper 80s.

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Set up for negative air exhaust and positive air intake. Both filtered. Then you can go from negative to positive at the click of fan speed as there are times you may want it reversed. But its the most ideal to have both filtered intake and exhaust. And its so cheep to do there is really no reason not to.

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TomDan…Same here.
I open tent up during lights on and place 9"fan blowing into tent.

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I am growing in the garage. It is not connected to the house and is shaded in the morning. If it is sunny then heat doesn’t start to build up until mid day. I have the power turned down to 80% and a clip-on fan aimed at the tops of the lights full time. I also have an exhaust fan in the top of the tent running all the time. My tent has screened openings at the bottom, so there is always air flow bringing fresh air in the bottom and taking the warm out of the top. The tent is only 5 degrees F warmer than the ambient air in the garage. It warms up in the afternoon and when it gets to 90, I open the door. The garage has vented eaves so it cools back down quickly in the evening. I also have the light driver mounted outside the tent. The gals are handling it pretty well. I have a third fan running on the canopy.

If a cannabis plant can survive under a hot summer day at 110° for a week long period during the summer with no issues 85 is no problem in fact I run my tent at 90° some days no problems not one issue in years so yes your plants genetics where you get your genetics not stable genetics weak genetics crappy nutrients and proper nutrients if you use them to worry about heat I’d say watch Dr Bruce he’ll explain a little more better than me and you’ll understand you won’t stress no more about your little heat

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