New Grower UVB light

[1guy1plant]

I have been researching uvb lighting to supplement my Leds. I just wanted to make sure I am on the right track. I ordered a 26 watt uvb light bulb and I plan to hang it without any type of reflector over the center of my 4 plants about 12 inches above the plants. I am at day 36 and I will run uvb about 4-6 hrs a day up until the last two weeks of my grow.

 

[jackmc]

Please let us know how it works for you. I've been looking at small UV lights for curing fingernail polish. What type of bulb did you buy and where did you buy it?

 

[Wienerwoods]

I've read about this also. It's a common and annoying misconception that you should use UVA and I'm glad you've done some homework.

If I were you, I'd look into a reflector since a lot of the light would be wasted without. I'd also run it for the whole duration of the light period until the very end. It's a matter of debate but I strongly believe that's the right way. I have no practical experience on using UV as I've just ordered a LED UFO that's supposed to have about 5W of actual UVB. Then again, it's a Chinese product so they might either cheap out with the lens or just use UVA because it's probably cheaper and I've no way of telling which one it is. I specifically requested for 380-415nm UVB, though.

But yeah, the theory is legit and I believe in the benefits. Good luck!

EDIT: I think you know this by now but 50 cm is the max. effective range of those things, so keep it close.

 

[TaNg]

You want to aim for 10% UVB so if your running 400w you want 40w UVB,this is according to Ed Rosental, you should only use it in late flower using it in veg is just stressing the plant.

 

[Feenix]

Here is an interesting vid on the subject with an explanation of the chemistry involved. It is a bit dated but I have not seen anything to dispute the science. From the Grow Show:

[video=youtube;lfiI78uN3Ks]https://www.youtube.com/watch?v=lfiI78uN3Ks[/video]

 

[1guy1plant]

Thanks for the video. It was interesting. I will let you guys know how it goes.

 

[medic grower]

Tang do you think Ed means 10% of the Actual Wattage Power or is it more like those Reptile Uvb bulbs with 2% 5%and 12% where 12 is for Dessert Animals which live in the Pure Sunlight. So i would guess the 10% is meant to the Ratio of Uvb gnereated thru the Bulb. Didnt had a Read o Eds Artcle bout Uvb but if You could link it or so Tang ...would be awesome.

 

[TRIPDOG]

I added a 23watt reptile cfl (UVB10) into my tent a couple of weeks ago. First week had it on for 15 main every hour. Now have it on 20 hours a day. Got 3 plants in tent each roughly 4 weeks apart. Not noticed any difference yet good or bad.

 

[mauricem00]

I've read about this also. It's a common and annoying misconception that you should use UVA and I'm glad you've done some homework.

If I were you, I'd look into a reflector since a lot of the light would be wasted without. I'd also run it for the whole duration of the light period until the very end. It's a matter of debate but I strongly believe that's the right way. I have no practical experience on using UV as I've just ordered a LED UFO that's supposed to have about 5W of actual UVB. Then again, it's a Chinese product so they might either cheap out with the lens or just use UVA because it's probably cheaper and I've no way of telling which one it is. I specifically requested for 380-415nm UVB, though.

But yeah, the theory is legit and I believe in the benefits. Good luck!

EDIT: I think you know this by now but 50 cm is the max. effective range of those things, so keep it close.

315 to 400nm is UVA. UVB has been shown to stimulate resin and cbd production and protect plants from insects.mold and fungus but true uvb diodes are very expensive ($122 for a 1/4 watt diode) mercury arc tubes and sunlight contain a small amount of UVB and at low levels (>%3) are beneficial thru the entire grow http://en.wikipedia.org/wiki/Ultraviolet and also see http://www.plantphysiol.org/content/160/1/145 a VERY SMALL reptile light would would be beneficial thru the entire grow.MH and fluorescent lights contain a small amount of UVB so supplemental UVB lighting would not be useful with these lights

 

[Groff]

315 to 400nm is UVA. UVB has been shown to stimulate resin and cbd production and protect plants from insects.mold and fungus but true uvb diodes are very expensive ($122 for a 1/4 watt diode) mercury arc tubes and sunlight contain a small amount of UVB and at low levels (>%3) are beneficial thru the entire grow http://en.wikipedia.org/wiki/Ultraviolet and also see http://www.plantphysiol.org/content/160/1/145 a VERY SMALL reptile light would would be beneficial thru the entire grow.MH and fluorescent lights contain a small amount of UVB so supplemental UVB lighting would not be useful with these lights

What do you mean by true UVB? I know they may not be pure UVB, but I was under the impression that the reptile lamps push out huge amounts of UVB. I mean, if they work for living animals they surely must work for plants.