If you’re growing photos I would not disturb or open tent during dark time. I think you would be fine for one day to roll your lights from day to night. @Hellraiser do you have a suggestion on the best way to roll from day to night on the light schedule.
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I’d give them an extended day, leave light on til the new dark period starts, then resume 18/6. In veg, they won’t really care much but I like the extended day over an extended night, since plants count the night hours and not the daylight hours.
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I have one in the room. I did have a box on the ac with duct work coming out of it and ran it into the tent. Found the best way, stated above, is to cool down the temp of the room and left it be sucked into your grow tent
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@Konflict happy anniversary and have a good weekend.
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I ran one of those portable coolers in my office for awhile. I have a ton of computers online. I switched to a mini split system in the office 2 years ago, and its paid for itself. These portable units (at least my 7 year old one) are effective, but given the size of my windows and the lack of a good sealing kit I found I was letting in hot air all day. Power bill would increase about $75 a month when on.
Now on the split system, when I used to run it all the time it would only add $25 a month. Then I switched from those blurple lights that put off a ton of heat to newer Mars TSL-2000 and I haven’t had to even turn on the extra AC unit. With lights similar to yours my room would reach 94-100 degrees during lights on and 75 lights off. Now the highest ive seen is 85 during the day.
I would first spend money on making sure your exhaust is good, but 10 degrees above ambient is pretty good. Then switch the lights to ones that aren’t producing as much heat. Then address any additional HVAC needs after reducing the heat off the lights.
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I have a somewhat unique situation and need advice. New strain grows much taller than my small 2.3’x2.3’ Mars Hydro tent can handle. The strain was at least 6’ tall when it switched to flowering stage about 3 weeks ago, much sooner than expected and it was growing outside here in Shenandoah Valley of Virginia. My plan was to grow one of the 4 plants in grow tent.
I just set up new 4’x4’x6.67’ Vivosun tent in a long narrow storage shed. This is not your typical box store DIY put together. Has gabled roof with shingles & at least 2x4 wall supports spaced about 14” apart. I insulated along back wall and side walls where tent is positioned. Never had moisture problem in there but it gets very hot.
Before moving plant into tent I have fans running with sensors monitoring the environment. Current reading inside tent is 99.7 and 37% humidity. New Mars Hydro 4” Intelligent fan is working at top speed with air currently vented out of tent into the shed. Small oscillating fan is on floor in front of open panel drawing air in which is hot shed air. This setup obviously won’t cool it down. Do you think a small portable ac unit would cool tent down enough. I’m not opposed to cutting small hole in back of shed for venting but funds are limited. There are two very small windows at back of shed, too small for window unit. Is there a relatively inexpensive portable ac unit that could be ducted outside the tent?
Obviously it is too hot for a flowering plant to be in that heat
This chart shows where you want your environment to be during the different stages. I realize you’re focusing on the heat, and i would too… But IMHO… any lower than 45% humidity is asking for a stall out on flower growth. Do that only at the ripening stages… About cooling…Unless you can window mount and go cheaper, Locate a dual exhaust portable ac so the circulation of fresh air is not returning the dank smell outside… It’ll be the version with two hoses.
I don’t know if you have it figured out but I had the same problem and this is what I Came up with.
I have a portable ac with hose amount the window and a little Vivosun bucket fan with a splitter to have it feed into 2 tents . Carbon filter and exhaust fans at the top of both inside the tent. I would come home and it would be 90 so I’m supper happy with what I came up with here .
I was having a very simial issue with themps getting into the mid 80s. I have a 5x5 tent. That is in a 10’x15’ room in my basement. Originally i planned on using my 6" inline fan to suck hot air out of the tent while opening a vent at the base of the tent to pull cooler air in. Wasnt hetting the temp down enough. I ended up getting a cheap window unit off craigslist($50) cutting a hole in the wall to mount the ac unit. Ac unit fills the room (lung room) with cooler air. Exhausts to a seperate room with fans and a window to prevent mold. I bought a cheap 30$ adjustable inline fan to pull the cooler air in to the tent while the inline fan pulls hot air out. Humidifier in the tent keeps the RH where it needs to be. Hope this helps. If not i can send pics of it when i get home.
Keeps everything nice and even
Oh man, didn’t notice the original date…hope you got it by now 
To grow marijuana plants indoors successfully, you have to plan and prepare well. Your plants need the ideal environment to flourish, which includes the proper temperature, humidity, carbon dioxide, ventilation and smell management.
You also have to balance ventilation and air-conditioning. You want enough airflow but also stable temperature control. A good grow tent is also essential.
I advise to take a look at our article about creating the best climate indoors for your marijuana plants.
That said, I also recommend to read our guide about ventilation as well.
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Good job logan im proud of you. Keeping it real 
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Hey all, been running into similar issue here with my tent, but it’s getting into the high 90s with the temp here in central TX. I have a small portable AC unit that I put in there and have it running with water but it doesn’t seem like it is really helping much. does anyone have any recommendations for a good one that would be powerful enough to cool a 4x4x6 tent in garage. my plants were doing well and then we got hot again and im trying my best to salvage them if I can. One might be dead from previous issues but seeing if I can revive it if possible.
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I have a portable ac unit similar to yours. I built a full header off of it and split the lines because I’m running two tents. 5’ x 7’ and a 4’ x 5’ Vivisun. Both I picked up for for a couple ozs. I slot and run 4” lines in my ac and just keep it on 80. I live in Pensacola and got my tents in an old corrugated 12’ x 12’ tin building. It’s took me a while to get dialed in but it’s on now.