UV Suppliment Lighting

bodhipop

Well-Known Member
Can you guys help a UV newbie?
I'm moving away from my California Lightworks Solarstorm 440 LED with UVB.
I'll be switching to a HLG 300 rspec or a Spiderfarmer light. What would be the best way to get some UV back in the mix efficiently?
 

Merlin1147

Well-Known Member
Some reference material for cannabis and UV.
If there are any other papers anyone wants access to just give me a shout and I'll see if I can get them.
Awesome reading. Thanks for the share! Since you asked! Can you find any cannabis papers on the use of red and far red to achieve an Emerson Effect? Also would be interested in seeing papers on the use of far red at the end of day in order to increase daylight hours and or reduce maturation time. Thanks in advance.
 

nunyabidness420

Well-Known Member
Awesome reading. Thanks for the share! Since you asked! Can you find any cannabis papers on the use of red and far red to achieve an Emerson Effect? Also would be interested in seeing papers on the use of far red at the end of day in order to increase daylight hours and or reduce maturation time. Thanks in advance.
I can help get access to the papers, but the research part is still up to you.
I'll need the name of the paper you want to get.
 

Kassiopeija

Well-Known Member
Awesome reading. Thanks for the share! Since you asked! Can you find any cannabis papers on the use of red and far red to achieve an Emerson Effect? Also would be interested in seeing papers on the use of far red at the end of day in order to increase daylight hours and or reduce maturation time. Thanks in advance.
Now that's really difficult, and basically, next to impossible for a homegrower as it would imply to have to measure in leaf-photosynthesis rates via O2-evolution. What is conventionally dubbed as "Emerson enhancement effect" (for example, in the SIMPLIFIED wikipedia-version) is nothing but an artifact caused by a better electron-transport during Emerson's experiments - however, there is absolutely no guarantee you'll always get this. There are studies which even suggest that at high ppfd levels it may even stiffle PS rate (note: PS rate does NOT equal dry harvest mass - as studies for YPFD suggests).
The Emerson-effect is much more complex and is basically the result of an increased widening of the photosynthetic action spectrum mentioned in the scientific standard literature by Emerson, Rabinowich, Govindjee et al up to 780nm via currently still unknown and very complex mechanisms (there are dozens of factors influencing the absorption spectrum of the LHCs - mostly causing redshifts - into IR light).
Lots of people think FR effects is only due to the phytochrome-effects (and for EOD treatment that holds true) but actually these photons (esp. 700-740nm) exzitate PSI so the debate is actually to use the wavelengths during the daylight regime as well.

More later...
 

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Galvatron1

Member
Awesome reading. Thanks for the share! Since you asked! Can you find any cannabis papers on the use of red and far red to achieve an Emerson Effect? Also would be interested in seeing papers on the use of far red at the end of day in order to increase daylight hours and or reduce maturation time. Thanks in advance.
 

UpstateRecGrower

Well-Known Member
Should the UV be used right up until the last day of bloom? Or should the plant be given a short period of time to recover from the stresses of UV?
 

UpstateRecGrower

Well-Known Member
Can too much uv cause airy buds without burning the fan leaves? I’ve been getting airy buds.. my light may have been too intense the first time but the second time definitely not.. my canopy temps were 90f max but I run co2 also so..
 

graying.geek

Well-Known Member
I think I mined this thread sufficiently to get an idea how to get started, but I'd appreciate a reality check. I have a 2' x 4' scrog canopy with 400w of bridgelux 4000'K strips over it, and I've embedded a 34" Reptisun T5 HO UVB at the same level as the strips. I haven't been able to find the % UVA/UVB for these tubes, but from what I can glean, I should run the lights 8" - 10" above the canopy, starting out the final 6 weeks of flower at 2 x 30 minute intervals of UV, increasing it every couple of days by 15 minutes until I can finish the last couple of weeks with 2 x 2-hr intervals. Sound right to those who know?

TIA.
 

Rurumo

Well-Known Member
I think I mined this thread sufficiently to get an idea how to get started, but I'd appreciate a reality check. I have a 2' x 4' scrog canopy with 400w of bridgelux 4000'K strips over it, and I've embedded a 34" Reptisun T5 HO UVB at the same level as the strips. I haven't been able to find the % UVA/UVB for these tubes, but from what I can glean, I should run the lights 8" - 10" above the canopy, starting out the final 6 weeks of flower at 2 x 30 minute intervals of UV, increasing it every couple of days by 15 minutes until I can finish the last couple of weeks with 2 x 2-hr intervals. Sound right to those who know?

TIA.
I was considering doing something very similar, since I have a bunch of those bulbs around for my turtles. I probably read a lot of the same threads, but that sounds like a good plan for them. I'm a little intimidated by the output of the agromax bulbs so I was thinking of trying something a bit less powerful....but I do love the idea that you can treat PM with the agromax bulbs. So many things I want to try...let us know how the Reptisun works for you!
 

graying.geek

Well-Known Member
I was considering doing something very similar, since I have a bunch of those bulbs around for my turtles. I probably read a lot of the same threads, but that sounds like a good plan for them. I'm a little intimidated by the output of the agromax bulbs so I was thinking of trying something a bit less powerful....but I do love the idea that you can treat PM with the agromax bulbs. So many things I want to try...let us know how the Reptisun works for you!
I can say from experience, you have to be somewhat careful with these Reptisun UVBs. I tried using this same config two grows ago, last winter, and was rewarded when both plants hermi'd and I ended up with a fully seeded canopy. Having a 1/2 pint jar of fem Durban Poison seeds is great, but I expect my problem was caused by running the UV tube too close to the canopy -- 4-6 inches. I had nanners coming out everywhere from plants that had never shown the tendency before, so I have little doubt it was caused by too high intensity UV. It has taught me to be cautious, ask questions, and listen to the right people.
 
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bigmikey86

Well-Known Member
I just finished up a run with the 10.0 reptisuns. Two 48” zoomed ballasts configured into my board set up. Worked great at 18” above canopy but almost too great, got quite a few brunt tips on the sugar leaves that made trimming a cunt. Frost galore though.

I ran it from week 3 to the end of week 8, started at 4 hours a day ramping up to 8 which was too much for this strain at least. I would feel more comfortable next run starting at 1 hr and ramping up to 4.

Granted this was at 18” above canopy, anything lower would be out of my experience.


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count zero

Member
I have a 2' x 4' scrog canopy with 400w of bridgelux 4000'K strips over it, and I've embedded a 34" Reptisun T5 HO UVB .... 8" - 10" above the canopy,
What's the wattage of those lamps? seems too close for the size. At that distance i reckon you'd want like 10 watts.
If you have more short on pulses, you can mitigate too strong an intensity, but you'll wear out the bulb quicker.
Or you just get two bulbs, mount them at 20", and loose like 20% of the UV in the shade of the strips. But hey, now you're disinfecting the ceiling too!
 

graying.geek

Well-Known Member
What's the wattage of those lamps? seems too close for the size. At that distance i reckon you'd want like 10 watts.
The 34-in tubes are 39w. As you point out, I'll lose a LOT of UV by putting the tubes above my strips. Maybe I should have gone with the 25w T8?
 

Norml56

Well-Known Member
I just finished up a run with the 10.0 reptisuns. Two 48” zoomed ballasts configured into my board set up. Worked great at 18” above canopy but almost too great, got quite a few brunt tips on the sugar leaves that made trimming a cunt. Frost galore though.

I ran it from week 3 to the end of week 8, started at 4 hours a day ramping up to 8 which was too much for this strain at least. I would feel more comfortable next run starting at 1 hr and ramping up to 4.

Granted this was at 18” above canopy, anything lower would be out of my experience.


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Do you typically get that fox tailing with that strain?
 

count zero

Member
The 34-in tubes are 39w. As you point out, I'll lose a LOT of UV by putting the tubes above my strips. Maybe I should have gone with the 25w T8?
I think that at 10" even the 25w are too much unless u're only dosing minutes at a time.
I don't know that you'd loose "a LOT" by going higher, depends on the heatsinks of your strips,
20% isn't that relevant loss for UV b/c it's not on all the time.

When u arrange several strips, you'd leave wider gaps in the center of the canope, as not to create a big hotspot in the center.
This would work towards 1 UV tube solution.
 
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