quick question about CFL lights. I know 6500k for veg 2700k for flower, but I see alot of logs with mixed spectrums. is this better than just switching bulbs? I've got plenty of both spectrums, I just want to know what is best for the plants.
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quick question about CFL lights. I know 6500k for veg 2700k for flower, but I see alot of logs with mixed spectrums. is this better than just switching bulbs? I've got plenty of both spectrums, I just want to know what is best for the plants.
during vegetative stage, the type of light doesn't matter as much ... the typical 'vegging-lamp', with 'cool/blue' spectrum, produces less stem-stretch ... but, that depends on the wattage/lumens, too ... my 400 HPS vegged just fine, no significant stretch, at all ... but, during the more critical flowering phase, the 'warm/red' spectrum is much more recommended ... it mimicks the Autumn sun, setting lower on the horizon, etc. ... I grew a couple crops with HPS (red) from start to finish, worked out just fine ... I also owned a $90 'full-spectrum' growlamp, that wasn't visibly any better, than a generic $12 HPS bulb ... :smokin:
Reaper knows his stuff for sure. I mixed some CFL spectrums with a 400w MH conversion bulb during veg stage and ended with just HPS. The results were just fine considering a 65 day seed to harvest AF white dwarf is drying already. So veg stage seems less important, flower stage I'd say spectrums mean a lot more.
thanks for responding reaper. so far I've kept them seperate, and the ladies are really happy. I just want the best yield I can get with cfl's. eventually I will get a HPS either a 250 or 400. but for now I'm just getting my feel for indoors. I've done some outdoor grows in the past, and never considered an indoor grow till I saw this site.
nice cola, there, 420 :thumbsup:
thanks 420! I kept them on 10 6500k cfls for 4 weeks of veg, and they've been on 10 2700k cfls for 3 weeks of 12/12 now. so far, I'm thrilled to death.
hey guy's, another quick question. a buddy of mine has some t-12 fluoro's he's wanting to use in his grow. I looked up the bulbs, and they have a 4200K color temp. I know some MH bulbs have the same temp, so would these be good for flower or veg? Or could he use them the whole grow? He's going to be using mainly CFL's, but thought these could help. How should I recommend to use these?
I used fluorescent tubes for many years, used the typical 'cool-white', too, not knowing any better ... the plants still grew OK, but, again, the warm, red spectrum is best, for flowering ... GE calls their warm, red spectrum tubes , the 'Kitchen & Bath' version ... as far as fluorescent lighting goes, I much prefer the tubes, over the CFL bulbs ... I always used the plain T10, or T12, the added lumens of the more expensive T5, just didn't compare for me, 'dollar-per-lumens' ... been a long time since I compared lumens/prices, the situation may have changed by now ... :smokin:
he had some bulbs left over from something else. so you think they'd be ok for veg and not for flower?
you will get less stretch, during the first 3 weeks, with 6500k...and T-12 floro tubes are about useless after that...IMO.Quote:
Originally Posted by fluid69
cool, thanks pimp.
What about using 4' t12s and changing lamps at flowing? Any good?
Quote:
Originally Posted by jimmy21
you could use them for supplemental lighting i suppose.Quote:
Originally Posted by Dutch Pimp
-shake
If you change to 2700k you get 3000 lumens of 2700k flouresent light. What's the difference between that and 2 2700k 27 watt cfls?
change what to 2700K? where do the 3000 lumens come from?
with the CFLs you're gonna get ~3200 lumens (depending on the output, obviously.
-shake
change from 6500k to 2700k depending on vegging or flowing.
what im saying is you guys say 4' t8's are worthless during flowing, but i don't see the difference between 2700k flouresent light from a cfl or 2700k flouresent light from a 4' t8 lamp
i checked my electrical supply house and t8s come in 3000k and 7300k
3000 lumens is the output of a 32watt 4' t8 lamp. So a 4' tandem t8 is putting out 6000 lumens. almost as much as 4 27watt cfls
am i wrong in my thought process?
the comment was about t-12s. and IMO = In My Opinion. so dutch was giving his thoughts.Quote:
Originally Posted by Dutch Pimp
my guess is dutch doesn't like the t-12s because they are so big you can't get as many close together as you can t-5s.
sorry to put words in your mouth dutch. please slap me if wrong and share!
-shake
I agree 'shake
T-12 floros are very weak. Excellent for the first 3 weeks with seedlings. After that, T5 or T8 high output floro tubes are needed; or CFL's or HID. IMO. If you want serious buds.
For some reason I read t8s. Ya t12s are junk. But since we are on the topic.â?¦. What would be the ideal kelvin temps? We use 2700k and 6500k because that's what cfls come in. But t8s don't. The lowest I could get was 3000k and then there was no 6500k. Just 5000k 7300k 7500k and 8000k
What would be best?
where are you looking for these bulbs at? i know you can get 6500K, t-8 bulbs at walmart. and i'm pretty sure they have 2700K (might be 3000K, or they might have both, haven't looked in a while) bulbs as well. they say it right on the front of the package.
-shake
3000k would do as well as 2700k...and 5000k would do as well as 6500k
it's not a perfect science...sometimes, you have to round off the sharp edges..:stoned:...(with floros)
would 5000k or 7300k be better for vegging? maybe a combination of the both?
and shake, i don't want to say your mistakin for sure, because i havn't looked, but cfls come in those, but i checked several manufactures and 2700k and 6500k may come in some special lamp, but for GE, philips or sylvania didn't have any in their catalog
i'm not mistaken, you just didn't look hard enough. no worries. i already have lights.
6500K. they don't make a 2700K, it was 3000K, like i stated it might be above.
good growing.
-shake
also, lookey what a little google search returned. 2700K t-8s. this was one of about 109,000 returns. so they must exist.
look a little bit harder.
-shake
those are t12's
but searching google, it looks like they do make them, for special "plant lights" but not for the 2.00 a standard lamp costs
hmmm, well i stand corrected. i'll have to see if my local walmart carries them. Like i said my electrical supply house couldn't get any without a special order
no worries man, we are all here to learn! if i get grumpy sometimes just ignore it. i'm getting old and have no patience.
-shake
not to jack the thread but i read some place that the uv rays that mh lights put out helps in the trich production when used with hps lights . i also read that the day light bulbs put out more uv than the cool white or the kitchen and bath bulbs. so my question is ; would it help to run a few 6700k cfls in with your 2700k or 3000k cfls during flower ?
a lot of people who use fluoros use a mixed spectrum. it is actually recommended. 75%/25% (75% 2700k, 25% 6500K).
if it's as simple as that then you could just throw in a uvb bulb. this is a highly debated topic 'round these parts.
i've got one that i'm thinking about throwing in my flower box. as soon as there is room.
-shake
If your MH bulb is behind glass, (in an enclosed hood) your ladies are getting virtually none of the UVB. Matter of fact, the glass envelope (the glass part of the bulb) inhibits the UVB before the light exit's the envelope...unless the envelope is cracked, which is a bad thing.
Always use common sense with using UV bulbs. They will cause blindness, and may cause skin conditions if precautions are not taken and adhered to.
Standard and "grow" CFL's and fluoro tubes emit no discernable UVB. UVB bulbs (reptile or tanning lights) emit UVB, and some of the more dangerous UVA.
Instead of worying about specific ratings, a general range is fine. 6000 to 7000 or so for veg, 2500 to 3500 or so for flower. No need to get all anal about specifics here, as different strains will react a tad different under the same spectrums...but not enough to ever worry about. If that worried...go with HID's. (MH or HPS)