UV A And UV B In Late Flower

Resinhound

Well-Known Member
Ya I have a reptile light its just a pain in the ass.Dumbass little 22in flouro tube,honestly cant be bothered to try and hang it.Its made to sit on a reptile enclosure I guess.
 

whitebb2727

Well-Known Member
Ya I have a reptile light its just a pain in the ass.Dumbass little 22in flouro tube,honestly cant be bothered to try and hang it.Its made to sit on a reptile enclosure I guess.
Most of the UV led stuff is for chemical curing, medical and sanitation.

If one were to take the time I'm sure cree makes something to fit the bill. We just got to find it and see about incorporating it into grow lights.
 

ttystikk

Well-Known Member
I'll take your educated conjecture over a lot of people's quantifiable data any day of the week. There's an awful lot about the way I grow weed that I can't quantify either, but when Week 10 or Week 12 or Week Whatever rolls around, the weight is there. And I can even explain how I did it, but I can't write it down and teach someone else how to do the same thing and achieve the same results.

Thanks again for the info. I'm going to be really interested in seeing how this progresses for you. I don't know anywhere near as much about this as you do, but on a gut level I know that where you're going with this is exactly where I sense that the future lies.
The future is COB LED. This is the present, which is still 30% more efficient than the recent past.
 

BobCajun

Well-Known Member
I think it will be quite a while yet before UVB LEDs get low enough in price to be practical. The fluorescent tubes would need to be about 1-2" from the plants, the intensity drops off so fast. Seems to me that reptile CFLs are the only practical UVB source right now. A CFL is like a straight tube but compressed into a much smaller area, therefore it has usable intensity at least 4x as far away as the straight tubes, judging from the output specs I've seen. You would also need a reflector to increase intensity by about 3x, and it has to be plain aluminum, not white, because white absorbs the UVB.

Good thing the reptile CFLs are available or it would be very inconvenient and probably very costly to use UVB on Cannabis. With the rep CFLs, pretty easy really, and not all that costly. It would be nice if they cost the same as regular CFLs but it's still affordable. Whether the results are worth the price, you would have to try it and judge for yourself. Nobody will believe anyone else anyway so pretty much have to try and see for yourself. I can tell you that two 13w tropical UVB CFLs in a half sq m cab and about a foot from the tops, with only the flat top of the cab covered in foil as reflector, does pretty much nothing. But then that was tropical UVB, which is pretty weak (I bought the wrong kind by mistake the first time, shit!), and only 13w. This time I'm using two 26w desert bulbs, plus I made reflectors out of aluminum lasagna pans, so this time I should get an accurate idea of whether it works or not.
 
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Resinhound

Well-Known Member
I wont be including UVB in my grows until there is a cost effective led option if ever...why?

Because I dont want to hang a bunch of cfls 2 inches from my plant with lasanga pans as reflectors,or dangle some tubes .Id rather my grow light doesnt have to compete with a bunch of cfls and makeshift reflectors....I just dont think UVB matters enough to fuck up my grow room.If It's merely a matter of 1 hit vs 2.ill just take 2.
 

qwizoking

Well-Known Member
"Itd be cool to see side by side of flowering times structure etc. Involving cry genes being hit etc

They dont work the same, uvr8 specifically increases certain precursors that can increase terp content. Uva could help im not sure or through what pathways

If this is the route youtake ie not.just growing weed but a more sciency approach or optimizing. an increase in blue light could aid photolyase activation. I would definitely use in conjunction but again see top of post"


Has anyone done uva side bybside and what was noted




Didnt read thread
 

whitebb2727

Well-Known Member
I think it will be quite a while yet before UVB LEDs get low enough in price to be practical. The fluorescent tubes would need to be about 1-2" from the plants, the intensity drops off so fast. Seems to me that reptile CFLs are the only practical UVB source right now. A CFL is like a straight tube but compressed into a much smaller area, therefore it has usable intensity at least 4x as far away as the straight tubes, judging from the output specs I've seen. You would also need a reflector to increase intensity by about 3x, and it has to be plain aluminum, not white, because white absorbs the UVB.

Good thing the reptile CFLs are available or it would be very inconvenient and probably very costly to use UVB on Cannabis. With the rep CFLs, pretty easy really, and not all that costly. It would be nice if they cost the same as regular CFLs but it's still affordable. Whether the results are worth the price, you would have to try it and judge for yourself. Nobody will believe anyone else anyway so pretty much have to try and see for yourself. I can tell you that two 13w tropical UVB CFLs in a half sq m cab and about a foot from the tops, with only the flat top of the cab covered in foil as reflector, does pretty much nothing. But then that was tropical UVB, which is pretty weak (I bought the wrong kind by mistake the first time, shit!), and only 13w. This time I'm using two 26w desert bulbs, plus I made reflectors out of aluminum lasagna pans, so this time I should get an accurate idea of whether it works or not.
Cfl is weaker than t5.

I have a feeling that you are very new to growing.

I wont be including UVB in my grows until there is a cost effective led option if ever...why?

Because I dont want to hang a bunch of cfls 2 inches from my plant with lasanga pans as reflectors,or dangle some tubes .Id rather my grow light doesnt have to compete with a bunch of cfls and makeshift reflectors....I just dont think UVB matters enough to fuck up my grow room.If It's merely a matter of 1 hit vs 2.ill just take 2.
Your wouldn't have to do all that. The uva bulbs I am using now I can feel on my skin from a couple feet away and I can tell a difference in plant growth with the seedlings. You take that uva/uvb bulb from agromax and I'm sure it has strong enough out put for a couple feet.
 

Resinhound

Well-Known Member
Cfl is weaker than t5.

I have a feeling that you are very new to growing.


Your wouldn't have to do all that. The uva bulbs I am using now I can feel on my skin from a couple feet away and I can tell a difference in plant growth with the seedlings. You take that uva/uvb bulb from agromax and I'm sure it has strong enough out put for a couple feet.
Ill look into it thanks man.What % UVB are those?
 

testiclees

Well-Known Member
The agro max and the hortilux are about the same price. Anyone have any thoughts on which would be better value? Im about to replace a single arcadia t5 48".
 

pinner420

Well-Known Member
The full spectrum ultra every other socket. 30 bucks a bulb. Didn't realize they'd expanded their line so much. Then the spectral 3000k in the other.
 

whitebb2727

Well-Known Member
The full spectrum ultra every other socket. 30 bucks a bulb. Didn't realize they'd expanded their line so much. Then the spectral 3000k in the other.
I found a hydro shop about 2 hour drive from here that has the hortilux t5 bulbs for $25 a pop and I get a 10% discount for being ex military.
 

BobCajun

Well-Known Member
I wont be including UVB in my grows until there is a cost effective led option if ever...why?

Because I dont want to hang a bunch of cfls 2 inches from my plant with lasanga pans as reflectors,or dangle some tubes .Id rather my grow light doesnt have to compete with a bunch of cfls and makeshift reflectors....I just dont think UVB matters enough to fuck up my grow room.If It's merely a matter of 1 hit vs 2.ill just take 2.
True that it's inconvenient. CFLs only need to be about 8" away though. But it's every grower's own call what they want to use.
 
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