Lighting watts per square foot question.

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First, I want to thank everyone for how helpful they have been. I am so glad I found AFN. Good vibes all around. I have my first three seeds germinating and I can barely sleep at night for wanting to go check on them.
I recently got rid of my 3'L x 2'w x 3'h grow box and converted the closet it was in into a small grow room. The room is 5.25ft wide and 4.75ft deep and has a 9 foot ceiling.I have three DYI light fixtures each hanging from ceiling that are adjustable to any height needed.Each fixture has a small dyi reflector and (8) 23-26w cfls (mixed spectrums) When I calculate watts per square foot I am only at approximately 24. I was at 50w per square foot in my grow box. My question is that with the fact that each fixture (184w) will be hanging directly over an individual plant, does the fact that I have extra square footage matter as the light will be directed at each plant. The walls are mylared from the ground up to about 5 feet but the space between the plants in center of room is about 2.5 feet.
 
First, I want to thank everyone for how helpful they have been. I am so glad I found AFN. Good vibes all around. I have my first three seeds germinating and I can barely sleep at night for wanting to go check on them.
I recently got rid of my 3'L x 2'w x 3'h grow box and converted the closet it was in into a small grow room. The room is 5.25ft wide and 4.75ft deep and has a 9 foot ceiling.I have three DYI light fixtures each hanging from ceiling that are adjustable to any height needed.Each fixture has a small dyi reflector and (8) 23-26w cfls (mixed spectrums) When I calculate watts per square foot I am only at approximately 24. I was at 50w per square foot in my grow box. My question is that with the fact that each fixture (184w) will be hanging directly over an individual plant, does the fact that I have extra square footage matter as the light will be directed at each plant. The walls are mylared from the ground up to about 5 feet but the space between the plants in center of room is about 2.5 feet.

Sounds like its time to upgrade to LED lights...lol! It makes no difference if your plants are centered under the lights. What it does mean, IMO, is that you could squeeze in another plant or two if you wanted. ( does spellcheck here now default to British? )
 
From my experience, bottom line, you'll need more light. You don't wanna go through a whole grow just to harvest some airy, under potent, under developed buds, when you can spend a few more dollars and get that primo smoke. Just my opinion.
 
Lol. I agree. I havespent as much on cfl’s as a nice 600w hid kit costs. The more I get into it thelarger my operation seems to get. I started off as 1guy1plant and I am now1guy3plants. Thanks for the advice.

 
* Lighting is not the easiest thing in the world for me to explain but I will do my best to help you, this is a disclamir for a lengthy wordy explanation.

The thing about lighting is penetration. The different lighting sources create different depths of penetration. Meaning that you have maximum lumens at say 6 inches with a 400watt 12 inches with a 600 and 18 inches with a 1000watt HID(I do not know nearly as much about CFLS or LEDs many others here do though and can probably chime in)

All that means is that if a 1000watt HID(or in your case a 184watt CFL) puts out X amount of lumens that is 18" away from the bulb, when you start to get further away the amount of lumens decreases exponetially(very very fast) so at 24" away you will have significantly less lumens.

Lumens make photosynthisis occur, so no matter how you position your CFLS there will be certain portions of the plant that are closer, thus getting more lumens and making more photosynthis, and some are further away getting less and making less.

So to sum up your question as stated above you really need more light, IMO and it is just that an opinion to get top quality nuggage 75 actual watts of lighting(no matter how you get it) is needed.

To give you a reference I have a total of 3.7m3 of space(very similar to yours) 8.5x4.5x9.0 and I have 2 1000watt MH/HPS's I am growing 6 plants in hydro. So I have a little over 300watts per plant or 533 watts per meter cubed. I will admit I might have overkill but again in my humboldt opinion I think it better to have too much light than not enough as I can always turn down my ballasts.

If you can get more lighting I think all here would agree to get more, if that is not an option try and position your lights as close to the biggest plant as possible and grow out 1 plant. I think you will get a better quality and yeild off positioning your CFLS around the biggest healthiest plant and make sure you keep your temps in check.

I hope this helps sorry for the book long post, good vibes comin your way for sure! Keep at it you will do well, it seems like you have a great head start!
 
Hi 1guy :)

I did okay grows with CFL but always had potency problems, even using a great 250W CFL with ten inch u-tubes.

Then i bought a 120W LED :

http://www.prakasa.co.uk/led-grow-lights/120w-led-grow-lights-seven-spectrum-by-prakasa

The grows were better than ok, the potency was better, but as someone said above, buds still airy, potency not the best etc ...

So i'm going for a 200W LED soon.

If you're going to spend months tending and nurturing then it's best to make sure it's worth it come harvest time.


All the best,

steely
 
Thanks guys. My budget is alittle tight right now bc I just ordered a fan and filter combo and some duct work, plus all the initial set up stuff over the last month or so.I started out thinking I would builda space bucket. ( www.spacebuckets.com)You can see where that has led me. I think I will hang a light proof tarp and block off half the closet until I can get a better lighting system. Maybe Santa will bring me one.
 
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