Norml56
Well-Known Member
Just a claim made by a user of the bulb on the agromax website. AgroMax UV Bulb
I use to LED, but now I CMH. for one main reason.
- Thread starter HolyGhost23
- Start date
Rurumo
Well-Known Member
Oh thanks for that, interesting. I might keep one around just in case I ever get PM again, seems like a fun experiment. I would have killed for these when I used to grow in a cold, dank garage.
dbz
Well-Known Member
How do you get to the plants in the back?
GrassBurner
Well-Known Member
Generally a few cusswords and a decent core workout
I used to do everything 1 handed. Lean into the cabinet and hold myself up on the back wall. Now I just take a plant or two out of the front. Any way I go its a pain in the ass. Ive got a small area in my loft and was trying to utilize all my space. Im fixing to build a new cabinet, with the main goal being ease of access.
NukaKola
Well-Known Member
From my understanding UVC is what is necessary to control PM. Outdoor plants can get PM quite easily despite the suns UVA/UVB rays. UVC rays don’t reach the earths surface because they are filtered by the atmosphere. UVC is what is used in water systems, ventilation systems, and hospitals for sterilization.
A 4’ T5 fixture, Agromax Pure UV bulb, and a cheap timer can be had for ~$50 and will last years since you are only using it for around 1hr/day. 3-5x cycles of 10-20min and covers a 4x4. Studies have shown 20-30% increase in THC/terps which is pretty big for the minimal investment and practically 0 maintenance.
jonnynobody
Well-Known Member
Efficiency like that gets my dick hard! I love how you utilized your space so efficiently. Kudos to you sir. Fine work.
GrassBurner
Well-Known Member
Thanks!! All the credit goes to RIU 
Plenty of people way smarter than me that have been willing to help 
It works great, I love these qb120's. Got 2 plants in 10 gallon pots going right now, hoping to get some big chunky cola's on them.
Plenty of people way smarter than me that have been willing to help It works great, I love these qb120's. Got 2 plants in 10 gallon pots going right now, hoping to get some big chunky cola's on them.
HolyGhost23
Well-Known Member
after going through a few grows with cobs to CMH, ive noticed that uv seems to make a difference in resin production. as for getting my hands on some qb120s or an other type of uvb fluorescent. wouldn't a lizard uvb cfl do the same thing? or a coral actinic t5?
ive read some grow journal with some Israeli scientist growing marijuana with all kinds of lights of all spectrums and found that 3500K with a full spectrum of uvb into near uvc range would be best for indoor grows,. though this was a book from the early 90's.
and cmh only comes in 3100k or 4100K. 3500K sounds like it be right in the middle.
ive read some grow journal with some Israeli scientist growing marijuana with all kinds of lights of all spectrums and found that 3500K with a full spectrum of uvb into near uvc range would be best for indoor grows,. though this was a book from the early 90's.
and cmh only comes in 3100k or 4100K. 3500K sounds like it be right in the middle.
Grow Lights Australia
Well-Known Member
We've done a few tests on this which have surprised a lot people. Namely that UVA, near-UV (400-420nm) and even blue light can stress the plant into increasing cannabinod production just as much as UVB – and in some cases outdo it, as UVB breaks down the cannabinoid precursor THCa as the plant produces it. That is why a lot of the oldschool growers used to harvest at dawn, after a long night, and why many indoor growers expose their plants to a 24-48 hour dark period prior to harvest. It is also why harvested plants are cured in a dark room.
These are results of our most recent round of cannabinoid testing. Can you guess which plants were under 6% UVB reptile bulbs, which ones were under CMH and which ones were under straight LED? I will tell you the answer later
SAMPLE.......CBDA.......CBD.......CBGa.......CBG.......CBN.......d9THC.......THCa
A...................................................2.2%........2%.........................4.4%.........14.3%
B...................................................0.9%........0.2%.......0.1%......5.8%..........21.3%
C...................0.1%.......................0.7%........................0.1%......1.4%..........24%
D...................0.2%.......................1%...........................0.1%......2%.............22.7%
If you want to read the answer for yourself, here is the original thread: https://rollitup.org/t/more-thc-testing-uva-vs-uvb-vs-near-uv.1010801/
And here is the thread that started it all: https://rollitup.org/t/thc-cbd-terpene-test-results-uva-vs-uvb-vs-none.1001617/
These are results of our most recent round of cannabinoid testing. Can you guess which plants were under 6% UVB reptile bulbs, which ones were under CMH and which ones were under straight LED? I will tell you the answer later
SAMPLE.......CBDA.......CBD.......CBGa.......CBG.......CBN.......d9THC.......THCa
A...................................................2.2%........2%.........................4.4%.........14.3%
B...................................................0.9%........0.2%.......0.1%......5.8%..........21.3%
C...................0.1%.......................0.7%........................0.1%......1.4%..........24%
D...................0.2%.......................1%...........................0.1%......2%.............22.7%
If you want to read the answer for yourself, here is the original thread: https://rollitup.org/t/more-thc-testing-uva-vs-uvb-vs-near-uv.1010801/
And here is the thread that started it all: https://rollitup.org/t/thc-cbd-terpene-test-results-uva-vs-uvb-vs-none.1001617/
hybridway2
Amare Shill
I'll have lab results in about a month. Cmh vs led before led had the uva. Next time, the winner of that will go against the braodspec led w/ uva.
Rn the led spectrum going up against x2 , 3k & 2, 42k , CMH is this:
Oh, can't post pics. Its the Canna-Spec by Amare.
Rn the led spectrum going up against x2 , 3k & 2, 42k , CMH is this:
Oh, can't post pics. Its the Canna-Spec by Amare.
hybridway2
Amare Shill
You
You are the man!We've done a few tests on this which have surprised a lot people. Namely that UVA, near-UV (400-420nm) and even blue light can stress the plant into increasing cannabinod production just as much as UVB – and in some cases outdo it, as UVB breaks down the cannabinoid precursor THCa as the plant produces it. That is why a lot of the oldschool growers used to harvest at dawn, after a long night, and why many indoor growers expose their plants to a 24-48 hour dark period prior to harvest. It is also why harvested plants are cured in a dark room.
These are results of our most recent round of cannabinoid testing. Can you guess which plants were under 6% UVB reptile bulbs, which ones were under CMH and which ones were under straight LED? I will tell you the answer later
SAMPLE.......CBDA.......CBD.......CBGa.......CBG.......CBN.......d9THC.......THCa
A...................................................2.2%........2%.........................4.4%.........14.3%
B...................................................0.9%........0.2%.......0.1%......5.8%..........21.3%
C...................0.1%.......................0.7%........................0.1%......1.4%..........24%
D...................0.2%.......................1%...........................0.1%......2%.............22.7%
If you want to read the answer for yourself, here is the original thread: https://rollitup.org/t/more-thc-testing-uva-vs-uvb-vs-near-uv.1010801/
And here is the thread that started it all: https://rollitup.org/t/thc-cbd-terpene-test-results-uva-vs-uvb-vs-none.1001617/
listener13
Active Member
Greetings from Michigan. I don’t usually post on cannabis sites and this thread interested me because uvb light is what creates More trichomes and thc on your buds. I have just switched to full spectrum LED lights myself and was thinking I might add UVB in flower. So far in veg, the plants love the LED’s. I am just not sold on the UV spectrum range they produce. UVB is 280-315 nm, UVA is 315-400 nm, UVC is 100- 280 nm. I think most are in that 315-400 nm range. UVB is a narrow spectrum range. I have heard good things about cmh bulbs producing the uv range needed in flower.
For years I have used tanning bulbs along with HPS Bulbs in flower and might continue using the tanning bulbs with the LED’s. I only used the tanning bulbs for 2-3 hours a day, in the middle of the day to simulate the brightest part of the day. Trichomes are light refractors that protect the buds and calyxes from becoming sun burnt. When UVB is introduced, more trichomes are produced by the plant. You only have to trick half the plant into thinking it is getting sun burnt for the whole plant to respond. My understanding is that the trichome then secrets more thc through a membrane in the bottom of trichome and up into the bulb of the trichome to help the light refraction process and protect the seed sites. In my case, great trichome production and high thc weed. Tanning bulbs have a 4‘ radius so two bulbs go a long way. The hex bulbs with built in reflectors do the best, just point them down.
For years I have used tanning bulbs along with HPS Bulbs in flower and might continue using the tanning bulbs with the LED’s. I only used the tanning bulbs for 2-3 hours a day, in the middle of the day to simulate the brightest part of the day. Trichomes are light refractors that protect the buds and calyxes from becoming sun burnt. When UVB is introduced, more trichomes are produced by the plant. You only have to trick half the plant into thinking it is getting sun burnt for the whole plant to respond. My understanding is that the trichome then secrets more thc through a membrane in the bottom of trichome and up into the bulb of the trichome to help the light refraction process and protect the seed sites. In my case, great trichome production and high thc weed. Tanning bulbs have a 4‘ radius so two bulbs go a long way. The hex bulbs with built in reflectors do the best, just point them down.
hybridway2
Amare Shill
From. My understanding & testing I've seen above from GLA (posted above). They show 450nm blue in regular led increasing thc. UVA will do the same thing & i believe, coupled with N/UVA (400-440)+470nm, it may be just as good if not better (due to simplicity). Simply adjust your timing ratios to be longer depending on the strength (umol) & nm you're using.
GLA shows us an increase in thc just using N/UVA in their High-Light boards.
Uvb is not necessary & just dangerous imo. Uva will ruin your retinas so where your glasses.
TimBar
Well-Known Member
the key to controlling PM with UV-B light is to do it after dark. PM is susceptible to UV-B control only in the dark. Best is to shut down your grow light an hour early and turn o UV-B lamp for just 2-18 minutes a couple times early in the night. Also best to have it followed up with 4 hours of dark. Many papers have been written on this.