1. We are currently experiencing issues with viewing and uploading images, our team is working on the issue.
    Dismiss Notice

14 plants, 11x12 room,.. how much light?

Discussion in 'Grow Room Design & Setup' started by DIYer, Sep 27, 2012.


    DIYer Well-Known Member

    Am growing 14 plants in a 11'x12' room divided into two sections. At the moment i have two 400w and one 600w HPS in the flowering area,... and 440w of CFL's and 300w of LED over the vegging ladies. I average around 40k Lux over the flowering canopy, around 8k over the vegging girls.

    My question is this,.. how much light indoors is enough?
    Never enough i know,.. but with direct sunlight being 100k Lux im thinking that's the goal? But do i really need to double my light? Currently my lights alone add $116 a month to my electric bill, which was $340 total in August, worst month of the year for me. The 7K BTU in the grow room makes up another $60 a month to the bill. I'm in a 1300sq ft apartment (smell is taken care of, plus im legal) just added the 600 HPS but i'm wondering if adding even more light would be recommended? I'd need more AC if i did. At what point does the electric bill start to gain attention?

    JayJammer Active Member

    You wanna shoot for 50watts/sq. ft. or more. This is a measurement of your canopy, not the whole room.
    I wouldn't recommend adding anymore lights in your apartment. The setup you have right now is more than enough for 14 plants.

    DIYer Well-Known Member

    I looked up 50w/sq ft, had never heard of it before. It does seem to be the goal folks shoot for, thanks for that info. So if i've got 1400w in my flowering area (400+400+600=1400) divided by 50, then i can grow over 28sq ft. Rough 6' x 5', which is exactly about how much my 6 ladies take up now.

    The flowering plants are being grown in six 20gal trash cans. HPA DTW setup. Given the 3 light sources i have to work with. Both 400's are in reflector hoods to the sides, the 600 is in a homemade cooltube reflector centered over top the canopy, all air cooled. What would folks recommend as the highest yielding method of growing my 6 ladies? I have one big mom flowering now that is taking up close to half my 6x5 canopy. Was running low on bud, it was my biggest lady and closest to flowering, so i gave it center stage and did some LST to it, spread it out pretty big and no doubt the other 5 around it are much smaller and wishing they had more light.

    SFguy Well-Known Member

    last months bill was 660 for me. just pay your bill. thats all they really care about they sell electricity im running around 3000 watts total.. a 400/veg 2x600's + 1000/flower, 100 watt t5 for clnes/ + pumps and fans and exaust blowers and a 8000 BTU portable A/C unit...

    DIYer Well-Known Member

    Ya i really don't think the bill will be an issue, just curious as to when some might know it became a tipping point.

    Below are pics, any input on how things could be better setup for more yield let me know.
    1.jpg Above...
    2.jpg Below...

    IMG_2429.JPG Few weeks into flowering, 95% white hairs still.

    michmed Active Member

    if there is a tipping point (which I've never really heard of in MI) it is going to vary by jurisdiction and/or utility company.

    If you are "legal" I wouldn't sweat it.

    If you are in a "legal" state I wouldn't sweat it much.

    Beaner Well-Known Member

    65 watts per square foot of growing space...it's simple...1000w covers 4x4 feet exactly 600 covers a 3x3 area perfectly and a 400 covers a 2x3 area...

    superstoner1 Well-Known Member

    i would do 2 1000's in each grow area.

    DIYer Well-Known Member

    Why two 1000's? Aren't 600's more efficient? Multiple light sources and all. Not that changing lights is an option now anyway im just wondering why anyone would prefer 1 single bulb over multiple ones like I've been going for.

    I'm pondering how to do a vertical grow with my cans and the 3 bulbs i have,.. if i even could,.. and if it would yield more per plant every few weeks, which is when i crop one and take a new clone. Got a bit of a perpetual grow going, not sure how that would jive with a vertical scrog...

    DIYer Well-Known Member

    i'm just going to state the obvious since no ones giving me anything else to say. stoner filled forums suck for getting real advice!

    superstoner1 Well-Known Member

    you got advice, and didnt like it. you didnt ask for so-called most efficient, but id put a 1k against a 600 any day.

    budwich Active Member

    I would say 2 600s instead of 1 1000.

    Organicuz Member

    To me it seems, (and I know that light gets progressively weaker the farther away you get, but), if any area of light underneath the useful 3'x3' portion of the canopy is overlapping the other lights useful area, then there should be about 1200w worth of light in that area. In your situation if you have them side by side [pic:_ _] only about 8" of light is overlapping on each side (36"light-20"length of reflector=16"of light outside of reflector.. 16"/2= 8" light to the right and left of each reflector) so 8"+8" = 16" which means you have 16"x36" of overlapping useful light which is about 1200w, and the rest is still 600w. This is why your plants in the middle are doing so well. If you had the lights side by side width wise [pic: | | ] touching - lets say in theory, there would be 36"-6"diameter of reflector=30"/2=15" overlapping on each side, 15"+15"=30", there would be 30"x36" useful 1200w light and only 6"x36" 600w. This would be the only way that using two 600w lights would be more efficient than a 1000w. If this it totally wrong someone plz correct me but logically it makes sense to me. I hope this helps...

    Kush2180 Active Member

    Your plants seem to be drooping quite significantly, they look overwatered.

Share This Page