Need some help deciding on CFL's

So I've been reading everything I can get my hands on about growing for a little while. I grew a small harvest a couple of different times and to be honest it's been about 8 years since my last grow.

I have learned so much more about growing now and I can afford way better equipment so money really isn't the problem.

I have decided that just for the stealth factor and ease of use, I want to use CFL's. I have been looking into all sorts of set-ups, ballasts, lights, etc. There is just so many options out their. I have boiled it down to one set-up that I think will be safe for stealth,heat,wiring, etc. Here it is http://www.stealthhydroponics.com/product.php?xProd=196&xSec=40 I want to put this in a cabinet that will be 78"H x 48"W x 24"D. Do you think I will need just one of these or should I go ahead and get a second? I only plan on 2 or 3 plants at a time which will be for personal medicinal uses only.

From Ed Rosenthal:

In the new Skunk Magazine there was a question in the "Ask Ed" section that just made my night last night when reading it...



The question was:

I intend to grow a single cannabis plant in a space 1' x 2'. What light would you recommend? I was think of using four 30-watt compact fluorescent lamps. Will this be enough? Cost isn't an issue but I am deterred from getting a high pressure sodium [light] because of the amount of heat the bulb produces.

Answer:

As you mentioned, you have several lighting systems to choose from, including compact fluorescents and high pressure sodium (HPS) lamps. Among HPS lamps you have a choice between a single 100-watt lamp which uses a total of about 120-watts and emits about 8,800 lumens(73 lumens per watt) or a 150-watt lamp, which uses about 180 watts and emits almost double that-15,800 lumens (87 lumens per watt).

A 42-watt compact fluorescent (CFL) emits about 2700 lumens(64 lumens per watt). Four 42 watt CFLs use 168 watts and emit 10,800 lumens. Other size CFLs have a similar efficiency.

However, that is only part of the story. Plants use mostly red and blue light. Yellow and green light is of little use to them, so light that is emitted in these spectrums is wasted energy. Most of the light emitted by HPS lamps is in the yellow spectrum. Only a small amount of the emitted light is is in the orange or red spectrums, which plants use efficiently. Warm white fluorescents (2700 Kelvin) emit a greater portion in the red and orange sectors.
Although fluorescents produce only about 75% of the light per watt that the HPS does, the amount of light usable by the plant is equal or probably higher with the fluorescents. You may wish to experiment to see if adding a single cool white CFL to replace one warm white results in shorter, stouter stems and more vigorous growth. The reasoning is that warm whites don't emit much blue light, which the plants use for photosynthesis and to regulate their growth. The cool white bulb supplies the blue light.

My call for your unit would be to use several (three to five) CFLs with a total input of between 120-160 watts. Although the 150 watt HPS is a bit more efficient that the CFLs in total output, watt for watt the fluorescents provide as much useful light as the HPS lamp. Heat is another consideration. The HPS runs much hotter and emits more heat than the fluoescents.

Make sure to use reflective material around the garden so that any light escaping the garden is reflected back to the plants. Any light that doesn't get to the plant leaves is wasted.


Look at a lumen/watt ration of various CFL's. The higher the wattage of CFLs, the lower the lumen/watt ratio. This chart was submitted by Jerry Garcia, of RIU and edited for typos.

For example...

the 200w listed at 9250 lumens for a lumens/watt ratio of 9250/200=46.25

the 150w is listed at 7500 lumens for a l/w ratio of 7500/150=50

the 125w is listed at 6500 lumens for a l/w ratio of 6500/125=52

the 42w are listed for 2700 lumens, l/w ratio of 2700/42=64.28

I have some 26w that give off 1700 lumens for a l/w ratio of 1700/26=65.38

GE lists some 13w that give off 825 lumens for a l/w ratio of 825/13=63.46

So, according to these numbers the most efficient bulbs for growing are the 26w that emit 1700 lumens. If you used 8 26w bulbs (208 watts total) you'd be getting 13,600 lumens...4,350 more lumens than a single 200 watt cfl.

I suppose you need to purchase more sockets and cords and things to support 8 bulbs, but in the long run more lower watt CFLs seem like the way to go.

L I G H T S Page 7

Damn Roseman, you never cease to amze with your knowledge of general growing or this site, lol. I don't think I'm gonna get a much better answer than that. So, from what I gather from this, it would be more beneficial and probably cheaper if I just bought 2 of the reflectors and purchased my own lighting rather than spending more on 2 entire set-ups.

rreign said:

Damn Roseman, you never cease to amze with your knowledge of general growing or this site, lol. I don't think I'm gonna get a much better answer than that. So, from what I gather from this, it would be more beneficial and probably cheaper if I just bought 2 of the reflectors and purchased my own lighting rather than spending more on 2 entire set-ups.

Click to expand...

Absolutely,
Lowes and Home depot now have 65 wtt bulbs and 42 watt bulbs ,in 2700k and 6500k, and very very cheap.

look here page 7 and 8:
L I G H T S Page 7

It also depends on what bulbs you are using and how much lumens. I read that about 1200 lumens/ sq ft is minimum lighting. Around 3000 lumens is ideal.

You are growing in a 4ft x 2 ft space = 8 sq ft. You will need about 24000 lumens to effectively grow.

As roseman said 4 x 42w bulbs = 10 800 lumens which is half of what you ideally want.

I would buy two, and get 8 x 42w bulbs to run. It will be enough to grow nicely.

I have come to believe that 2 42 watt bulbs, in one Clamp Reflector is the most efficient, cost effective way to provide light to your Grow.
You also need one of these

and one of these

Thanks a lot with your help again, both of you. I will probably just buy 2 of the smaller 3 bulb reflectors from Stealthhydro and then buy the bulbs seperately. Either that or I'll just suck it up and buy the whole 420 kit from them. They say it has over 23000 lumens and offers (2) 5000k (2) 6500k and (2) 3000k. Or is that just too much light for like 2 plants

Too much light , is like too much pot to smoke!!!

There is a pound of dried manicured buds coming out of this closet in 4 weeks, under CFLs!

9 plants total,
2 giants about 44 - 50 inches tall,
4 mediums that are 38 to 40 inches tall,
and 3 runts.
In 5th week of 12/12 now.

Yeah, what was I thinking... LOL too much light, HA!!

i grew the plant in my avatar (pic taken last night) with cfls: (1) hooded 42 watt at the top with (2) 27w beside it, then i have 2 more 27 watters dangling near the plant with (2) 13 watt t-2 cool whites. above a foot above the plants i have a bathroom vanity strip with 5 13 watters in it. my plant is now 6 weeks old. im one week into flowering. what do u guys think????