If you would have posted that idea before I built it I probably woulda done it with the exhaust on top, that's a pretty good idea, except that when my plant is sleeping it is more susceptible to random light from wherever. I do keep it in my closet though, which I think keeps out most light anyway, although I've never closed myself inside it so I can't say for sure :P

But as far as the passive holes go and 2 exhausts, one of those fans by itself is rated at 34.5 cfm. My container can't be any more than 5 cubic feet, so it's air is being completely exchanged approximately 7 times per minute, plenty of ventilation I would assume. And not only that, I'm in an apartment building and smell will be an issue, so I'm keeping the flow constant and airtight in a way that no smell will escape aside from my exhaust. With passive holes, the place would most likely be reeking of dope. I'll be carbon filtering my exhaust when necessary. For now, I might as well not restrict the airflow.

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I believe that the greatest of minds were stoners.
Styrofoam cooler - first grow ever!

exhaust on top is a standard in grow ops...


You should get in there... you do not want light leaks... you could make a "panda film" cover for your box...

Did you notice the "glow" with the lights on?

Same thing happens from outside in...


Sure, but heat rises... and you have a trap up top... it will build up there if it cannot escape...

not to mention that that is an axial fan.. which looses cfm very quickly with ANY restriction... just not enough umph...


Get a carbon filter going when you flower... it will smell if you don't...

Anther standard in grow ops is to have more exhaust than intake (hence the passive intake suggestion)....

This creates a negative pressure in the box... any air leaks will be in the form of fresh air coming in... none escaping...

All dirty air is directed to the exhaust... and the carbon filter...


On the contrary...

WITHOUT them, your set up is flawed...

If you have the same cfm intake as exhaust and you restrict the exhaust with a filter, you are causing a positive pressure... meaning that the box is over full and air will leak out any possible way... spreading smell and building heat...



agreed...


go with what you now bro..

but I went from a Aerogarden, to a 20x36x54 600 watt tent with zero heat issues... to a full 2400w 2 pound a month room...

I am speaking from experience... even if I didn't look up the actual flashpoint...

Best of luck bro...

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I just finished a new shelf unit flowering chamber last night. I will shoot some pics if you like. It has the exhaust unit on top. I just put a throw rug over it.....no light leaks and temps are cool in my basement so no worries. Before we moved this plastic shelf unit was our laundry shelf.

GypsyBush, where were you when I was designing this thing anyway! haha, everything you told me in your last post are things I know and should have taken into account, but I was too avid to get this thing going, mainly because my little plant was suffering without a proper environment. Right now it is doing exactly what it should be, but yes with the carbon filter I completely understand where you're coming from. So Maybe to solve this problem I will hook up a dimmer switch to my intake fan and slow it down, either that or upsize my exhaust.. It's a little too late to shift my exhaust to the roof, but the box is relatively small and the circulation in it is really good, it definitely is pulling air from the top of the box so I don't think heat will be a problem. My exhaust is warm and inside my box stays cool. I've had it running for over 7 hours now.

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I believe that the greatest of minds were stoners.
Styrofoam cooler - first grow ever!

why is it too late?

and what is the temperature in there?

are you familiar with the GrowFAQ

and you should also read this... it's funny...

How not to grow dope

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I think it's too late because the hole for the fan is over 3 inches in diameter, it's big... Like too big for the 2 fans to keep constant flow the whole time, I know that smell would escape. I could put some sort of cover to taper it down some I guess.

Do you think it would work to just switch my intake around so that it pulls, and then put a couple smaller holes in the cover as passive holes? I think that way it would keep a steady negative pull, although that would mean i either need to route both exhausts into one filter leter on, or attach filters to both exhausts, both options sound like a hassle. I probably should have taken more time planning this out lol. But at least it's safe, right?

Edit: Oh yeah, forgot to mention, no thermo in there yet so I don't know how warm it is, but it's no warmer than the air in my room, when I put my hand in there the ventialtion actually makes my hand feel cooler than the ambient temp in my room - chill factor, i suppose.

And about the blue LEDs, they are so small and insignificant I doubt my plant will even register their flickering blue glow as 'usable light', what do you think?

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I believe that the greatest of minds were stoners.
Styrofoam cooler - first grow ever!

go with what you know bro...
There is a reason why all successful ops have exhaust on top and intake on the bottom...

it works...

I can't imagine why it's too late...

I would just drill 2 holes on the lid and put the fans on there...

I already explained this... I am not gonna repeat my self...

Your hand is not a thermometer.. without a thermometer, you are just guessing...

And it's not cooler in there.. I guarantee it... you have heat sources in a closed box... heat will build...

can you see it? so can your plants...

You need to read dude...

ALL of these issues are covered in the basic GrowFAQ

read and you will learn...

start here .. Noobs: If you fail to plan... plan to fail!



Gypsy out...

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Done

Yes it is Yours would be too if you had it trained.

I researched it, those particular LEDs are producing only a fraction of a single lumen EACH, dimly reflected inside the box when all other lights are out. There are a total of 8 LEDs in the fans, so the most possible light they could be getting is under 8 lumens. Are you saying my plants don't realize it's bedtime when it switched from 10 000+ lumens to 8?

Agreed.

Draw & Cut some new fan holes


Screw in fans, put lights back in.


Passive intake vents - I tacked a dryer sheet to the outside of this one,even though it's held very tightly in place by suction alone. Makes it smell good and guaranteed to create negative pressure with a slight restriction. The opposite side is just open though.


Finished, with overhead exhaust



I'm actually considering duct-taping the whole outside of the box (aside from vents obvsiously) so external light doesn't get in and internal light doesn't get out, although my closet is doing a pretty good job on its own.

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I believe that the greatest of minds were stoners.
Styrofoam cooler - first grow ever!

OK... Looks better on the ventilation... though when and if you flower, you do not want that smell on your buds... trust me.. it SUCKS to have dryer smell on buds...

and your hand is not train-able for temperatures... get a thermometer...

Are you familiar with a chemical process called PHOTOSYNTHESIS...???

It happens when LIGHT (any light) reaches the green surface of a leaf...

Bro... your plants don't sleep... they shift modes.... and if you confuse them (by having light hit part of the plant while other parts are in the dark) you will end up stressing the hell out of it, possibly even creating a hermie...

I'm sorry if I seem short bro...

I have a bum leg and it hurts like hell sometimes.... like now... so I get a little cranky and short, but I'm still trying to help with no desire to offend or prove anything.... just sharing the info....

so sorry if I seem rude... it's not me... it's the pain..

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Does the moonlight screw up outdoor plants then? I'm just extrapolating on your theory, I know what photosynthesis and how it works, but those LEDs are enough light for it to do anything at all. How does my plant know a firefly isn't sitting on it in the woods? :/

I will probably invest in a thermometer just for curiosity's sake, but I know the temperature in that box isn't too warm, the ventilation actually cools my lights! - after all a case fan is designed to cool warm components, and right now my box is exchanging all of it's air nearly 15 times/minute with fresh cool air from my closet, and now exiting out the top So far it's working awesome and I've already noticed a great improvement in both colour and size since my transplant yesterday. Anyway once I get the temperature it will probably be posted in this thread and I'll let you know, along with anyone else who may be wondering if my box is getting too hot.

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I believe that the greatest of minds were stoners.
Styrofoam cooler - first grow ever!