Newbie hoping for some basic lighting guidance

Hi all. Just trying to start my 1st grow and was hoping for some guidance in regards to set up.

I have a closet space roughly 40" wide by 30" deep with standard 8 ft ceiling. I’m looking for max yield (of course) so from what I understand I need the most light my space can handle. I plan to grow white widow feminized (ordered from ILGM) in soil. Maybe 2 plants scrogged if I can swing it.

My limiting factor is that I will not be able to ventilate with any duct work whatsoever. The normal ambient temp in my space ranges from 65-72 degrees. I was thinking maybe. 400 watt HID but am concerned about heat. So I considered getting 2 CFL lamps that each have 12 bulbs & throw 288 watts, so I’d have 576 watts of CFL light at manageable temps.

But then I see that CFL is not intense enough to really maximize yield during flowering. So I’m basically hopelessly confused & looking for help from anyone willing to spare a few minutes helping out a raw beginner. What light system would you suggest? Any other advice?? Thank you in advance!!!


You need about 400 true watts if you want to fill your space. I would highly suggest looking at LED (keeping in mind true watts). Without venting it’s going to get really warm/hot I’m afraid.

Example, Viparspectrum 900 is 418 watts. That’s just about perfect for your space. Does get a little warm though but not as much as other light sources.


I would suggest LED lights too, they consume a lot less electricity, with minimum heat and they last twice even third time the life expectansy of any other light systeme… you can buy one under 150$ and will be pay in one growth in electricity saving…:wink::innocent: I personnaly grow in a 2 /2 /8 closet and don’t have a duct systeme and i’m able to keep a temperature and a RH with the cannabis comfort zone… :wink: :innocent: :sunglasses:

Hope that you’ll find this helpful and useful :v:

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Thanks, I really appreciate the guidance.

Assuming I can get a 600 watt LED in there, which I think I can accomplish, how many plants do you think a space that size should house in order to maximize yield? And I’m excited to hear that someone else has a thriving grow in a similar sized space! Awesome! :sunglasses:

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Just looked up the viper spectra 900. Looks just about perfect, thanks again Matthew420! :slightly_smiling_face:

With that light in that space do you think I can raise 1-2 quality WW ladies from seed to harvest and produce some kind of decent yield? Sorry for all the questions but I’m excited & a little overwhelmed at the same time.

Also just want to say that from what I can see this is a very welcoming & very generous & helpful community so I’ll do my best to share as I make my journey and will return the favor one day if I ever figure out what I’m doing. Thanks again all.


Just a suggestion you may want to purchase two led light at half your target power to max coverage area .but 1 light is fine for 1 plant also you don’t need as much light in veg as you do in flower so you could power down durning veg save electric and heat build up
Just a suggestion
I run 4 led light to cover my 6x4 tent with option of adding more if needed but 4 seems to work great for me
Welcome and happy growing :+1::wink::wink:

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Personnaly I have a 1000 Watts LED and 1 is enough, however your closet is a bit bigger and like @Countryboyjvd1971 suggest, 2 LED to covert the area is a good idea but 1 with the support of 4 LED strips,1 on each corner of the closet should do the trick for less money than a second LED light…:wink::innocent:

You can grow as much as 4-5 plant in your closet, depends on the strains you choose, with 1-2 WW you’ll be just fine :+1::v:

I have 6 plants under (2) Viparspecta 900’s and (2) 4-tube 4’ fixtures in a 5’x5’ tent.

as @Countryboyjvd1971 said, you can also get (2) 1/2 size ones to help spread the light out a little more.

My tent/ lighting looks like this (older fish-eye shot)


My closet I use it 46"x36" for plant I grow 3-6 at a time. I have 2 mars hydro 600 and 1 mars hydro 96 led 1 mars hydro 300 reflector plus 8 150w cfls for lighting. 1 16" X 20" ac intake air filter for intake. 1 6" exhaust fan when lights on 1 4" exhaust fan on all the time just to keep cool


Thought this Mite help

you are needing to save some money and want to get only one light get the one 125 watt CFL (compact fluorscent light) and get it in the 6500 K spectrum, it will do fine in blooming flowering as well as vegetative growing. Yes it should do very well for that size canopy/floor space. With CFL lights you can do a real easy in your head estimation of about a minimum of 40 to 50 watts per square foot, and so actually about 125 watt. actually might be over kill, but it depends on how you are to mount the light, how much vertical space it will take up and if you can keep the temps down in such a small space. Even in a fluorescent light, 125 watts will put out quite an amount of heat.

The five 20 watt CFLs might be a better option for such a small grow but you might not save anything on heat. And in fact it may create more heat. Most of the heat with fluorescent lights comes from the ballast. In a CFL, this ballast is inside the vented plastic base. With so many lights, you have a whole lot of little ballasts that total wattage is 100 watts but the extra numbers of ballasts might create more heat than the one ballast in the 125 watt bulb. You might want to look into finding one 100 watt CFL in the 6500K for you size grow.

Here is some more information on fluorescent lights:



Thanks all for taking the time to help me out, I really appreciate it.

I have been giving serious thought to a CFL set up for the reasons Will mentions. I’m just concerned it may produce a significantly lower yield. What do you think?

Which set up, in your opinion, is more likely to produce the bushiest, healthiest, and highest yielding plants: LED or CFL’s? Main concern is that I don’t have ventilation (other than a small fan & opening/closing the door to my space), just hoping to grow one or two solid plants for personal use. So I am looking for whichever lighting option will give me the best chance at raising one or two very happy, healthy and high producing girls. And as always, thanks in advance for any help!

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I started with two cfls (125w and 250w) in a 4x2x6 tent. Got about 3 oz dry growing one GSC plant with 1/4 strength nutes. Upgraded to 1200w led and kept cfls for help below the canopy grew 3 GSC plants and doubled the yield using 1/2 strength nutes and bloom supplement. Upgrade came in on week 6 of flowering. Just upgraded again to cmh 315w thinking about adding the led with the cmh but that might be overkill. My cmh kit cost $250 led was $175 and both cfl kits were about $100 total for both sets.

For me it’s a no brainer : LED :+1::ok_hand::sunglasses::innocent::v:

First off Welcome to the best forum there is
Next LED is the way to go
Next heat will be and issue no matter what light source you end up using you need airflow in and out that would be where id start my setup making sure you Exchange air at the right rate next id like to recommend buying WW autoflowers very forgiving and i say this because with Reg Fem seeds in dark period in flower you could turn your hard work into something between male and female if you get my drift …autos are easy to learn with just set your timer and lite feeding when they start to flower which they do on there own ppl use different light cycles but 18-6 20-4 24-0 are top settings hope i helped also hit me up ill help with any other questions. .start with one or two plants

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If you can get some Fox Farms Soil

Thanks again Niala!

A few questions if you’d be so kind:

  1. do you have a recommendation for a particular LED brand and/or model?

  2. when you refer to LED strips in each corner of the closet, are they mounted vertically or horizontally?

  3. to maximize yield am I better trying to grow 3-4 medium sized plants or 1-2 that I really allow to veg?

  4. any wild guesses as to what I may be able to yield from a grow of this size using the LED setup?

Sorry for all the questions & as always, thanks so much for the help!

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Thank you Brian! And you are right - everyone in this community that I’ve so far had the pleasure of meeting has been amazing. So willing to help without being judgmental. It’s really really cool…

And thanks for the tips. A question for you as well if it’s ok: any suggestions to aid in air exchange given that I just really won’t be able to ventilate with any ductwork or actual vents? I plan to use small fan to circulate the air in there, and I’ll have the closet door open for a few hours each day, but beyond that I am at a loss…any insight would be appreciated. And as always - thanks man!

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Okay so is there and attic above the space and if yes i have my setup in a walkin closet and used a four inch hole saw to vent centrifugal fan with ducting keep the round blank from hole saw to replace later if needed

With that 4 inch all the air youll need will be sucked under the door like a vacuum it works my walkin is larger then your space and my temps are just right 75 lights ob 65 lights out

It’s ok, I like to help :wink::innocent: For the lights, it really depend on your budget. For under 200$ US, you can have these

    This is the one I use.

    This is the one I have order for a vertical mount to achieved maximum light penetration for bigger yielding.

  3. 3-4 medium size plant that you can do topping to maximise yielding.

  4. If everthing goes super well, without any problem a wild guess, you could achieved 32 ounce (2 lbs) of dry buds :heart_eyes::+1:

Hoping that you’ll find this helpful :innocent:

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