Temp Question

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Well-Known Member
Jun 28, 2011
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I'm 2 days into flowering and I have left the door open to the closet all day when veg but close it obviously for dark period now that I'm flowering. I have it from 9pm-9am lights on but I leave around 730 and get home 1030. I checked the temp and it was 98 with the door closed 78 with it open. If I only have the door closed for that small amount of time I shouldn't have any problems right?
They'll be stressed, but should pull through.

You could maybe flip the light schedule so it's on while you're asleep.

That miight mess with your daily rhythm though; having to sleep with blindfold, and the UV light on your skin may make it difficult.
I already have them on from 9pm-9am. They're off when I'm at work. Its only a couple hrs tho. I can't think of a way to solve this besides buy a grow tent
Yes, it WILL be a problem. You simply cannot let them get that hot everyday without stressing them. Do you have an air cooled light? What size/type of extraction fan do you have? Do you open the door when you are home? How do you keep the space dark (it needs absolute 100% dark)?
It sounds like you don't have any ventilation within the grow space. You must have some kind of ventilation in order to move the heat and stale air out and at the same time pull in fresh cooler air. Even if you have to rig up something temporary with some cardboard and cheap fans that would allow you to exchange that air. Through veg you have been able to get away with it, but going through flower, fresh air and temp control is critical. You may survive it like it is but the yeild will suffer by as much as half :( If you want to save your closet door, you can get some nice heavy cardboard from any of the big package stores or department stores that sell the large appliances. Using duct tape, you can make an artificial door so that you can cut a 4-6" hole in the top and the same in the bottom. then attach (with duct tape if necessary) a computer fan or some small fan that pulls good. You would have to create some boxes that can be attached that would block light and paint them with flat black paint to absorb the light. This would allow you to generate enough air exchange to eliminate the issue ;)
It is 100%dark when the door is closed and the door is open when I'm home bc thats when the lights are on and I close the door about an hr before the lights go off I have a fan in there but that just pushes the air in the closet around. I'll try and make a temporary fix with the cardboard as you said HP within the next 2 days.
Like Hushpuppoy mentioned, you need an exhaust fan--there is no substitute for it. Ventilation (exhaust) is for more than heat control, although you DO need some kind of exhaust for heat control. Plants need a continual supply of FRESH air all the time the lights are on for proper photosynthesis. The only real way to accomplish this is to exhaust old hot air. Just pushing hot CO2 depleted air around is detrimental to your flowering girls.
:yeahthat: But like Hushpuppoy said about the whole cardboard door and a temp fix for your issue until you can gather up enough funds for some proper equipment. :D
ok so I bought 4 80mm computer fans and have them wired already. Question is should I have

3 exhaust and 1 intake
2 exhaust and 2 intake
4 exhaust and 0 intake (just have an open hole but still protected from light)
I like to use active exhaust and passive intake. I pull the hot old air from the top of my tent and have 3 passive intakes along the bottom of the tent. Jmo
Ok its officially fixed. I did a test on the set up to see if it worked and it keeps the temp at 81-82 degrees. I have all four 80mm fans exhausting the closet with 3 passive intakes at the bottom. I also have a fan blowing towards the intakes just for a lil extra air. As you can see there are triangles with holes underneath and at the ends of the triangles are half-boxes to block out light. I went in the room and its a very...very faint glow of light. And don't make fun of my set-up its ghetto but it works


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Good job....nice to see someone actually use the advice provided instead of ignoring it and then complaining when their yield sucks.
Hamster Lewis said:
Good job....nice to see someone actually use the advice provided instead of ignoring it and then complaining when their yield sucks.
lol well said
Hamster Lewis said:
Good job....nice to see someone actually use the advice provided instead of ignoring it and then complaining when their yield sucks.

I'm under 23 yrs old too and I actually take advice lol unheard of haha. I appreciate all the advice you guys give me. I'm tryin to grow for a long time not just once so might as well take advice from pple who have already messed up and take heed to their warning. thanx again everyone
That looks like it is going to do you. Temps 81-82 will be okay.

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