Ok, so I've read a bit about lights, what type to use, when to use it, and so forth, but the question I have is how much? I understand that the more you have the better off you are, but generally speaking how many watts of light are you looking for per square foot? In addition to this, how many lumens of light are you looking for per square foot, and are the two (lumens and watts) related? Saying that I need 100 watts per square foot of growing space when working with an hps system, how many lumens is that? And if I were to use CFLs, some put off different amounts of lumens than others compared to watts right? So if I wanted to match the same amount of light that a 100 watt hps system puts out on a one square foot floor would I need 100 watts of cfls? I understand that the spectrums are different, and the plants react differently, but would the light levels be the same?

Again, I understand the more the better, but for many of us heat becomes an issue, especially those of us growing in smaller areas. So, generally speaking, how many lumens per square foot am I looking for?

from what i know the sun puts off ruffly 10,000 lumens per sq foot, and the sun gives the best light so what ever combination of lights you decide to use getting the lumens as close to natural without burning your plants would be best. the cfl's give off alot of lumens compared to the wattage they use, but because they are florecent, the distance the light travels is very short hence why you have to put them so close to the plant. and as far as how they compare to hid's the hid's actually give off more lumens per watt, but they do run hotter.

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And it depends on the amount of space you will be using. My first grow was under 240 watts of cfl's and like 17,000lumens. I am now using a 250w HPS light with like 29,000lumens and this grow is going to be way more bud at the end of this grow. You can even get away building one of those grow cabinets out of the rubermaid tubs. There is a thread on here somewhere that shows how to do it with cfls and they are getting the best yeilds with it.

ok, so if I were to say, roughly that I am shooting for as close to 10,000 lumens per square foot as I can get. The question becomes the good old classic CFL vs HPS. According to

Things to know about lighting

if I were to shoot for 10,000 lumens per square foot, and I were to use CFLs, I would need 143 watts of CFLs per square foot (10,000 lumens/70 lumens per watt = 143 watts), or roughly 6.5 23 watt bulbs (the largest ones I could find at home depot).

If I were to use HPS, and I were still shooting for 10,000 lumens per square foot I would need 93.5 watts (10,000 lumens/107 lumens per watt = 93.5 watts).

My grow space is rather small, and heat can become an issue, in all honesty I grow very few plants as my square footage is 1.7875 square feet. So in my personal situation, in order to cover the 10,000 lumens per square foot goal, I would need either 11 different 23 watt CFLs or one 167 watt HPS (I know they don't offer it in 167, so should I go with 150 or 200?). So which one would put off more heat, the 11 23 watt cfls or the one 167 watt hps, in theory at least?

you can keep heat under control with a homemade cool tube for the hps light and not really need to worry about it with a good exhaust setup.

I'm getting a 6" vortex, as that is the largest that I feel comfortable fitting in my cab right now, but I planned on dropping down the cfm a little bit to reduce the noise, and durring flowering using a carbon scrubber, which will reduce it even more. But Im just generally looking for which would produce more heat, 11 23 watt cfls or a 150 watt hps. I don't want to spend the resources on the hps to find out that it opperates at too high of a heat for me to deal with and end up going to the cfls.

that many cfl's and a 150 is a tuff one. but i would almost say the cfl's would give off more heat. but with the fan i don't think it would matter much, either way.

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Yea, i would have to say that too. A small hps light like that would probably give off less heat than that many cfl's. And i would only grow about 4 short plants under them.