Enviroment management help

Hey guys,

I really dived in head first with this grow; I tried to do as much research as possible before hand but I’m drowning right now.

First issue: too fucking hot
I have a 600w MH light within a 2’ x 2’ grow tent and it’s standing around 100F inside. My poor seedling was struggling. I moved the tent outside under our deck and opened up the door (it’s legal here, not worried about privacy) and I"m now able to keep it around 92-93 and the plant has tripled in size in the last week.

I have two 4" 240cfm fans, neither of them seem to do much inside as it raised the ambient temperature of the room to the point where the whole room was too hot (opening a window was not possible due to security reasons).

Thinking about switching my 600w MH/HPS light to 1000w LED. Do you have any recommendations on pot specific lights? I’ve seen a million of them on amazon but too much choice is a curse and I would appreciate some guidance. They also claim 1000w LED or 600w leds but only actually pull 100/200w… Does that mean they generate as much light as a 1000/600w led and only actually pull 100 or am I missing something? I would like the light to be able to cover my 2’ x 2’ grow tent and be able to provide enough light for up to 4 plants.

If you think I should stick with the MH/HPS light can you recommend a fan that would do the job? Trying to keep the solution under $150 if possible

I’ve got a couple more seedlings on the way

Na man the ones you’re probably are looking at (Chinese made blurple) state they use like 500 5w diodes therefor it means it’s a 2500w light… wrong. Only pulling 1-200 watts let along ppfd of what’s hitting the canopy. Many of us use quantum boards either DIY or hlg kits.

If it’s legal there I’d definitely plan an outdoor grow when season permits - much larger yields and cheaper of course. You could always get a portable ac for the room the tents in to lower heat. Amazon has decent ones for like 300$ or maybe search for a window unit locally?


Are you running both fans as exhaust?

I was running both as exhaust, one is 192 CFM and the other is just a 100CFM booster. I need better fans, but I’m worried about buying another one that doesn’t fix my problem.

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Where are you getting your fresh air and what is the temperature of the fresh air. Exhaust both fans out the top open flap on bottom ,if you haven’t already

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Your light is too big for your space. A qb 135 kit is about $200 and would grow out a 2x2 nicely. It’s a little more than your proposed budget, but would put you on cutting edge of led tech. No need to worry about watts or any of that garbage. The independent third party test data shows it to provide suitable par levels for 4 square feet.

You would be making something like 75% reduction in btu’s in your space. I’d say that would be a really good start in the right direction.


Fresh air is part of the problem. In my room I was unable to get airflow because I can’t leave a door/window open due to the logistics of the room. Therefore all the hot air being exhausted out was increasing the ambient room temperature over time.
EDIT: As for setup of my fans, I have one at the bottom and one at the top. With the tent being outside I just open the door. I tried with and without fans running and the temp didn’t change from 92/93F so I took them out while I try and devise a better system.

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Thanks a lot for the feedback, it is really challenging to navigate the market as I don’t want something decent; I want something good. Had the price been $187 I would have bit my tongue and made the purchase, but it’s $187 us (I’m canadian) which after taxes and import fees would be closer to $300 which isn’t possible right now.

I live with two engineers (mech and chemical) and all of us are capable of DIY projects. Maybe quality requires more money than I can afford right now but is there a cheaper alternative that you can think of? Or a website that you trust for reliable products?

Everyone claims to this and that and unfortunately it seems only experience can help navigate the bullshit.

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If you’re up for a DIY project, I can certainly help. I’ve helped a couple of friends from the north with DIY lights. Will be as good or better than you can buy without a doubt.

Do you have access to any inexpensive aluminum plate, angle, bar stock, or anything like that?

@dbrn32 Yeah we definitely have access to that. We would appreciate any help!

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Most build come out roughly about a dollar a watt unless u got some wire or hanging material or framing material ull save a few more bucks but a purchased 650 watt light is 800 pree assembled I could build one with better coverage for probally 100 less then that but then theres the pre made warranty factor that u dont get with DIY the new gavita 1700e is the probally one of the best lights out there for 1200 bucks but the only thing they got that mine dont is uv b diode which are supposed to increase resin gland production you need to think about what your long term goals are and spend accordingly no sence to spend money to take baby steps I spent probally 1000 dollar on stuff i wish i never bought before I found this forum

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You already have 2x2 tent right? And what exactly do you have for aluminum? The aluminum is growing to be used as heatsink material for your leds. So depending on exactly what you have or can get will decide what is good option for leds. Digikey ca has at least a few options.

I’ll talk to my roommate but he says he has access to a metal scrapyard. What would be an ideal piece? We have lots of tools as well.

Just did some research: we’ll check what’s available but could copper work as well or is it better to stick with aluminum for this job (he may not have access to copper but just in case).

Current items:

2’ x 2’ x 5’3” grow tent

4in carbon filter

4in booster fan

4in inline 195cfm fan

600w ballast

1x HPS bulb

1x MH bulb

Copper would work, but its awfully expensive. Most of the strips are either available in 280mm or 560mm lengths. So depending on what you come up with would need to accommodate that.

@dbrn32 We’ll stick with aluminum for now. I know computers quite well which is fing with my ability to conceptualize what size this heat sink is and if it is designed differently for lights. Can I use an old computer heat sink (have a couple lying around, some pretty big ones as well).

That thought aside, if we do chose to build one from scratch, should we get a couple sheets of the 540mm aluminum? Or have I misinterpreted something?

EDIT: Trying to do as much research as possible so I’m not a baby demanding food. I checked out the Slate V2 from Horticulturelighting (they seem to be one of the good sources) so I understand a little bit more of what I’m building. I’m sure using their diagram we could build something or is their a better way to do it?
EDIT V2: Found these on digikey " Description LED LM561C WARM WHT 3500K 4SMD " " Digi-Key Part Number 1510-1553-1-ND "

Trying to mimic the ones found on horticulture. As always, insight is appreciative.

I did some research into your profile and I can see you’re one of the main contributors of valuable information on this site and I personally want to thank you very much. It means a lot to me that you’d take time out of your day to share your knowledge with the community. Thank you.
PS I’m also reading through your other lighting threads to hopefully gain some useful insight.

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I didn’t really specify because there’s probably a lot of things we could make work. If you had a bunch of cpu coolers we could do cob build instead of mid power. I guess I was expecting to let you dig around and see what you can come up with cheap before suggesting something specific. I didn’t want to put you in a narrow mindset so to speak.

I have used stuff like 1/8" aluminum plate, 2" aluminum bar stock, 1" aluminum angle, heatsink extrusions from heatsink USA, pin heatsinks, CPU coolers, and probably a few other things too.

If you check out DIY lights around the forum I’m sure you’ll come up with several ideas. Then just keep your eyes peeled.

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@dbrn32 Just got a bonus today and I plan on putting some of it into the light so my budget got a little bigger. I’d be willing to spend around $300usd to either build a light or buy one. I was checking out the horticulture ones and I love the 135w model but I just realized my tent is actually 2.5’ x 2.5’ x 63" and apparently that is too small for that model. My friends are confident that they can build a heatsink and repurpose a power supply but they don’t understand how these quantum boards are or why they’re necessary.

There not nessecarry but theres alot of bang for your buck there

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It’s not necessary to use a quantum board. That is just what horticulture lighting group calls their pcb’s.

I will look and see what is in stock at digikey Canada


Digikey Canada has SI-B8U261560WW for like $22. You could do 8 of those on meanwell hlg-185h-c1050a.

That show leave you with roughly $60 or so to figure out heatsinks and wiring.