Grow tent temperature control

I have a 2x2x5 budgrower tent with Mars Hydro led. It is in the garage workshop closed space with a Pioneer split unit for temp control. Small fan inside tent. 4in. Inline exhaust fan and bottom ports open for air flow. I can’t seem to keep the temp steady with the tent closed. Temp rises slowly but steady. Ive had the room temp as low as 65 and still the interior of the tent gets too hot. I’ve been unzipping the tent door and am able to control temp that way. I know it’s not optimum to have tent unzipped, however I’m curious what effect that might have on my plants and other thoughts on how to remedy this situation

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you can try freezing a couple gallon jugs of water & leaving them in there , is your 4’’ in line pulling alot of air through? & can you pull in air from outdoors directly to the tent? I live upstate ny & temps have been challenging, this time of year we vary from low 30s to mid 70s.

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Thanks for the tip. I’ll give that a try. I’m thinking maybe my inline fan is not pulling enough air through.

try these few things…Lights on at NIGHT, when it is cooler, off during warmest part of the day. It does NOT hurt to have tent OPEN unless
at dark time - you are letting in ambient light that will affect the flowering of your plant
I open my tent during the day. Most lights, especially LED, are narrow and only have to shine on the plants. What escapes does not do much anyway…
What is you light model?
Is the SPLIT INSIDE the tent or are you using input / output ventilation tubes…they throw a ton of heat as exhaust…gotta vent that somewhere
what is TOO HOT? you can handle up to about 82°f without co2…maybe even a little higher if you have enough air circulating and they are the right strain…so what strain?

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I had the same problem with the 4 inch fans and my setup is in a bedroom in my house so temperature outside the tent is not the issue. I stepped up to a 6 inch fan on my small tent and all is good now.

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Thanks for the info. I’m growing Northern Lights auto flower so light won’t be an issue. I’m just glad it won’t hurt the plants to have the tent open. The split unit cools the workshop it is not inside the tent. One grower mentioned putting frozen jugs of water in the tent, that seemed to work earlier today. However I think maybe a larger in-line fan might be a permanent fix. Will I need to changeThe carbon scrubber it’s flange is 4in. Thanks for taking time to help a newbie.

Thanks I had a feeling it might be the fan

I didn’t answe a couple questions you asked. I read that above 85 was too hot. Your opinion?

I’m not sure about the particulars of the light. I bought a turn key tent from the budgrower online and the only thing showing is Mars Hydro. It’s an led light.

Above 85 is too hot unless you are supplementing with CO2…I use frozen plastic gallon containers but it is only a bandaid…
If it is a MarsHydro, there will be a manufacturing label on the light…please look
carbon scrubber flange…you say it is a 4" flange…You can get a 6" fan, new tubing and a reducer flange from 6" down to 4" but it might be just as cheap to get a new 6" carbon scrubber…

I offered $90 and did a second offer at $95 that was accepted…
Good units, I have already ordered 2 of these and a third through a friend that he bought…

I’ll check the light again, I think The Budgrower where I bought the tent removed all stickers and labels to encourage purchasing directly from them, just a hunch. I’ll check light again. Thanks for the link to the fans I’ll check it out. Thanks again for your time and expertise,

Hey Mike!

Thanks for your post, long before IG, this is all we growers had! Let’s get to your issue, I read some post reply’s an they said 82F with lights on (that’s with co2 n if poster said my bad, but important to note). I don’t go above 77F during day, n 69-70F at nite in flower. I use to leave my tents open, but ur cheating urself of precious lumens n a stable environment for ur plants. I think your issue may be your fan isn’t strong enough for job or add an intake or another output fan to help with airflow. Also, I see lots of ppl just “vent” their tents, make sure that old air is removed from room n some way for fresh to enter. I think a 4” is too small for most setups, but I also like moving a lot of air. Best of luck n feel free to DM for help👍

Thanks for your response. I’m researching fan set ups for the tent. Any brands you recommend? I rely on the bottom vents for inflow and in-line fan for outflow. Would it be better to use the current 4 inch for inflow and the néw 6 inch for outflow or just add a 6 inch in addition to the 4 for outflow. Again the tent is 2x2x5. Your advice is much appreciated. Very helpful people on this site.

with today’s led’s, Only at an angle of 0-5° can the diode assume 100% light intensity. Unless you are using sodium or halogen lights, a hood / reflector directs the light to a more narrow pathway to increase intensity to the SWEET SPOT. Led’s of today have such a narrow beam width that open tents do not really diminish the available light for a plant greater than 15-20% and even then, only on the outer edges of the plant. When PAR readings are done, notice the QUICK degradation of the amount of photons / par levels as you move just inches outside the sweet spot at the sweet height. Even high powered led’s lose over 75% of their photon penetration ability once beyond 35°angle off center. The outer edge of the par value rarely is over 200 from a 3-400w light at 18". What is lost outside the tent or not reflected back is less than nominal…

Happy to help my friend! I’m gonna tell u, I ONLY use in-line booster fans (my setup is much bigger n I move so much air I don’t even use auxiliary cooling or heating n I live in the desert)!
If your not running HPS/HID lights you don’t need those crazy expensive fans. I’m familiar with ur tent n here’s what I would do. As far as booster fans go (get a 6” or 8”, whatever naturally fits ur tents output vents/openings n the duct to support it n some duct tape) but shld have at least a few exhaust over 4”). Regardless it doesn’t matter two 4” exhaust will work if need be, but keep in mind bigger fans move more air of course.
Next, get remove your intake fan, but still leave the intake ports open (I just put in a little duct to size so it forms to your intake openings). Make sure you have all your other intake areas open as well.
Now I’m rly plain when it comes to booster fans, but literally do some research bc it shldnt b more than 20-40 tops per a fan. Currently I’m rocking some older vivosun booster 8” fans as my exhaust from tent n then have another booster I worked into ceiling to vent the room. I like n have used same setup for ur tent, use the exhaust fans to pull in the fresh air (as if you have a intake n outtake fan running at different speeds they will fight each other n screw up the flow), n vent out ur room somehow so u always will have fresh air exchange.
Hopefully this makes sense, and lemme know your progress, but I know it works as I’m constantly running super happy and healthy plants. …I’ll b posting up on here soon also, n the meanwhile I’m here to help y’all! :+1::v::green_heart::mage:‍♂

For most part I agree with what you mentioned, definitely directional lights more so that a hanging hps bulb with it putting light off in every direction. But my lights are up high due to plant height n I’d lose quite a bit, plus tents r made of Mylar inside for a reason. I’ve done the PAR test as well n if I’m even missing out on 5-10% of light n more n reflections I don’t wanna give even that up.
Still have many awesome gromies that do crack tents still, so as I like to say to each their own, and as long as it works, then that’s more that enough.:+1::v::green_heart:

I would go with a AC Infinitely 6’ if you don’t want alot of noise and they are a great fan in my opinion :wink: and I’ve been though some fans…

Thanks for your info, the 6 inch is what I’m going to get. Thanks again