How Many Cfls For 2 Plants?

trytops007

Active Member
its not how many cfl s you need for plants it really depeneds on many factors ... eg size of box ...

the size of plants you want them to be ...

post the box dimensions of the width , depth , height
 

jackonthebox

Well-Known Member
I have 8 on mine right now but def would liked to have more through-out the grow. I think I could be satisfied with 12 but even more would be better.
 

Peg

Active Member
Lol, i've been using 12 16w, and 12 26w for my 4 hindu kush plants and they seem to be sitting sassy at a month old. Wiring is a bit of a clusterfuck though :p
 

Peg

Active Member
yeah, i cant help but agree with you. I spend most of my time perusing ebay in search of that "perfect deal", but have never had such luck. School costs money, and its hard to convince people to just give you things :p Non-the-less I s'pose I'll make the switch here someday. We'll just see how many 100watters I can duct tape to my setup before shit hits the fan and I get fed up.
 

heywhatsthatsmell

Well-Known Member
ive been using cfl's for awhile 5 30w for 1 monster i plan on switching to hps when i move. you can get 400w at insidesun.com for 100 bucks
 

badman2424

Well-Known Member
right know i have 4-26 watt bulbs and 2-40 watt, when my 2 plants get a little bigger im going to put 2 more 26 watt bulbs on them 4 a total of 236 watts,more light tighter buds!
 

Skitzotic

Well-Known Member
i only have 5 cfl's energy saving bulbs. they are 23 watts a peice. 1600 lumens a peice. But, because of lack of wattage, im keeping them nice and close to the plant, like an inch away from my seedlings right now. But on the front it also says .its equal to 100 watts on a non energy saving bulb, so that would be the same as 500 watts, and that will be close up to the plant, hopefully it works out. They will go outside eventually
 

entropic

Well-Known Member
You can't compare it that way.

23w CFL = 1600 lumens = 69.6 lumens/watt
70w HPS = 8000 lumens = 114.3 lumens/watt

Also light intensity decays according to the inverse square law, here's the forumla:
Inverse Square Law: Brightness at distance A = (brightness at distance B) × [(distance B)/(distance A)]2. Position (B) is the reference position.

A lamp that puts out 1000 lumens at 1ft puts out 1000 * (1/2^2) = 1000 * 1/4 = 250 lumens
At 3 feet that same lamp puts out 1000 * (1/3^2) = 1000 * (1/9) = 111.1 lumens

CFL's produce more heat than HPS but disperse it over a wider area.
HPS have better canopy penetration.
HPS are more efficient.
HPS produce more PAR (photosynthetically active radiation) than CFLs.

So summing up, 23w CFL ≠ 100w worth of light, it's 23 watts. At 1600 lumens a piece and 115w total that's 8000 lumens. You're fine with the light for the vegetative state, but come flowering time I'd add at least a 70w HPS but a 150w one would be better and they don't cost much more. You'll be more than pleased you bought one when harvest time comes. With 8000 lumens from the CFLs and another 16000 from a 150w HPS you'll see a major difference in flowering and a gigantic difference in harvest.
 

Skitzotic

Well-Known Member
Its it a good idea to leave the lights an inch or 2 away from the plant?
There loving it right now, there poppin up like crazy
 

Peg

Active Member
i keep my 100 watters 2 inches away ... plants dig it ... only worry should be the heat. Too hot ... and you'll notice :(. If you can keep your hand on it for a while I wouldn't worry too much. Most of my plants I let grow into my floro tubes due to the low temps and I haven't had any probs.
 

goodgreen

Well-Known Member
i keep my 100 watters 2 inches away ... plants dig it ... only worry should be the heat. Too hot ... and you'll notice :(. If you can keep your hand on it for a while I wouldn't worry too much. Most of my plants I let grow into my floro tubes due to the low temps and I haven't had any probs.
u use floro through whole life
 
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