Club T5

So I had posted a while back about running 16 4' t5's in flower, but due to those agromax pure bloom lamps being out of stock at the time I was ready to buy new lighting, I ended up going in another direction. I was going to spend $350 on two 4 lamp 4' ho t5 fixtures and 8 lamps (including four hortilux powerveg UV lamps) anyway, so after some research I picked up a 1000w Galaxy DE ballast, a Solistek 1000w DE 10k Finisher lamp, and a cheap DE wing reflector for $385. The ballast and lamp can run at 750w which is less than the 864w the 16 ho t5's would be pulling, but can also be overdriven to 1150w which some claim provides the best spectrum/impact on plants as a finisher (higher UV output?). This will be an experiment in its own right and I'll be using 432w of 6500k and 3000k t5's i already have to reduce electricity usage/light the tent when I am working nearby because this 10k finisher puts out a lot of UV. Note that there are some threads out there related to running MH lamps in open reflectors being dangerous. While I can't find any evidence of anyone actually being harmed by a MH lamp in an open reflector after light searching (and I used to run a 400w MH that way when I was younger and completely oblivious with no ill effects), I will be taking the precaution of never opening the tent (or really being near it) while the 1000w DE MH is running in the open wing reflector. The open reflector is possibly beneficial due to the UV filtering effects of most glass. This solis tek 10k is made with low-iron glass that doesn't absorb UV and supposedly it will sunburn you in short order.
Anyway in my reading I came across some info that leads me to believe 5000k t5 bulbs could be superior to 6500k for veg due to having the same amount of blue light, less green, and more red. I also learned that standard t5 fluorescents are not at all actually full spectrum lights, they would more accurately be described as tri-spectrum lights as the light they put out is almost entirely in 3 narrow bandwidths. This is because they are using the same three gases in every standard lamp, just in different ratios to get different kelvin temps. Every spectral graph of every standard t5 i can find shows the same pattern of the vast majority of light being emitted at about 440nm blue, 545nm green, and 610nm red. I think this explains why t5's with a high kelvin rating are so effective in veg - the blue light they emit is in the ideal range for blue. This combined with the excellent efficiency of ho t5's makes them perfect for veg. There was a guy on another site saying that buying all 4100k or 5000k lamps was the same or better than mixing 6500k and 3000k because all these t5's emit the same frequencies, simply in different proportions that appear as different colors to the human eye and brain. He was saying that since you want uniform light distribution, its just easier to buy all 4100k or 5000k lamps than mess with mixing lamps unless you have reason to believe a kelvin temp of, say, 4750k (what he calculated the 50/50 mix of 3000k and 6500k to be, not sure if it really works that way) is actually better than 4100k or 5000k.

http://www.tcpi.com/spec-sheets/
(Note that the kelvin temperature on the spec sheet for the 4100 54w T5 model says 3500k, I can only assume it's a typo.)

The above link (go to linear lamps and ballasts) makes it easy to open up spec sheets for the different kelvin temps as tabs in your browser and click through them to compare the graphs. Most graphs from other companies show even more dominance of the three dominant wavelengths and less radiation emitted in other ranges than what is shown in these graphs. What I am seeing is that the percentage of blue light (about 25% or .05 out of .20 in the 3 dominant frequencies) is the same in 6500k and 5000k bulbs - the same amount of blue. The only thing that changes is that green goes from .10 out of .20 to .09 out of .20, and red goes from .05 to .06. More red, less green. This would seem desirable, yes? When you move into the lower kelvin temperatures, the blue becomes a smaller portion of the total light and since blue is the fluoro's bread and butter for growing those compact healthy plants we know and love, this would seem undesirable.
The question I have when it comes to flower is, how good is this 610nm red light for flowering? How much of the growth of buds grown under a mix of 6500k and 3000k lamps is coming from the red and how much from the 440nm blue that is still present even in the 2700k lamps? If the blue is driving growth, how much red does it take to stimulate flowering? It would be interesting to test all 4100k lamps (with a higher percentage of blue and green, and a decent amount of red) vs all 3000k lamps.
Many graphs showing only chlorophyll a and b, or showing individual pigments, seem to treat 610nm red as being nearly useless for plant growth, but other graphs showing overall plant absorption show 610nm red as being in a pretty good part of the red spectrum, or even the very peak. The McCree curve has 610nm at the peak of the graph for "average plant response". It comes from a 1972 academic paper from the journal agricultural meteorology and is often cited by LED manufacturers; it is referenced and linked on the wikipedia page on PAR.

http://plantphys.info/plant_physiology/images/psnpigmentspec.gif
http://www.marigoldlighting.com/wp-content/uploads/2015/03/PAR-Curve.png
http://pinklightaeroponics.net/wp-content/uploads/2014/02/Photosynthesis-Absorption-Spectrum.gif
https://www.google.com/search?q=545nm+wavelength+light&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiu8a25m7TMAhVR4mMKHbEpCJMQ_AUIBygB&biw=1433&bih=748#tbm=isch&q=nm+wavelength+light+plant+absorption&imgrc=LW5TZyGJ4i-8rM:
https://en.wikipedia.org/wiki/Photosynthetically_active_radiation

One thought that came to mind is that the 610nm is slightly higher frequency than the pigment graph's ideal reds that vibrate a little slower. Could it be that the 610nm red slows down slightly as it bounces around in the tent , in the canopy, and in the leaf, thus providing a pretty good usable red spectrum in the process of dissipating into heat? There is some ambiguity about the effectiveness of 610nm red light in driving plant growth, at least for me, because I don't have any experience using all 3000k lamps successfully. Input from anyone with a lot of experience using 2700k and 3000k t5's would be great to illuminate this for me. Do they drive growth on their own or is more blue (higher kelvin temp) better for yields as well as for maintaining healthy plants?

Thoughts?
 

RM3

Well-Known Member
So I had posted a while back about running 16 4' t5's in flower, but due to those agromax pure bloom lamps being out of stock at the time I was ready to buy new lighting, I ended up going in another direction. I was going to spend $350 on two 4 lamp 4' ho t5 fixtures and 8 lamps (including four hortilux powerveg UV lamps) anyway, so after some research I picked up a 1000w Galaxy DE ballast, a Solistek 1000w DE 10k Finisher lamp, and a cheap DE wing reflector for $385. The ballast and lamp can run at 750w which is less than the 864w the 16 ho t5's would be pulling, but can also be overdriven to 1150w which some claim provides the best spectrum/impact on plants as a finisher (higher UV output?). This will be an experiment in its own right and I'll be using 432w of 6500k and 3000k t5's i already have to reduce electricity usage/light the tent when I am working nearby because this 10k finisher puts out a lot of UV. Note that there are some threads out there related to running MH lamps in open reflectors being dangerous. While I can't find any evidence of anyone actually being harmed by a MH lamp in an open reflector after light searching (and I used to run a 400w MH that way when I was younger and completely oblivious with no ill effects), I will be taking the precaution of never opening the tent (or really being near it) while the 1000w DE MH is running in the open wing reflector. The open reflector is possibly beneficial due to the UV filtering effects of most glass. This solis tek 10k is made with low-iron glass that doesn't absorb UV and supposedly it will sunburn you in short order.
Anyway in my reading I came across some info that leads me to believe 5000k t5 bulbs could be superior to 6500k for veg due to having the same amount of blue light, less green, and more red. I also learned that standard t5 fluorescents are not at all actually full spectrum lights, they would more accurately be described as tri-spectrum lights as the light they put out is almost entirely in 3 narrow bandwidths. This is because they are using the same three gases in every standard lamp, just in different ratios to get different kelvin temps. Every spectral graph of every standard t5 i can find shows the same pattern of the vast majority of light being emitted at about 440nm blue, 545nm green, and 610nm red. I think this explains why t5's with a high kelvin rating are so effective in veg - the blue light they emit is in the ideal range for blue. This combined with the excellent efficiency of ho t5's makes them perfect for veg. There was a guy on another site saying that buying all 4100k or 5000k lamps was the same or better than mixing 6500k and 3000k because all these t5's emit the same frequencies, simply in different proportions that appear as different colors to the human eye and brain. He was saying that since you want uniform light distribution, its just easier to buy all 4100k or 5000k lamps than mess with mixing lamps unless you have reason to believe a kelvin temp of, say, 4750k (what he calculated the 50/50 mix of 3000k and 6500k to be, not sure if it really works that way) is actually better than 4100k or 5000k.

http://www.tcpi.com/spec-sheets/
(Note that the kelvin temperature on the spec sheet for the 4100 54w T5 model says 3500k, I can only assume it's a typo.)

The above link (go to linear lamps and ballasts) makes it easy to open up spec sheets for the different kelvin temps as tabs in your browser and click through them to compare the graphs. Most graphs from other companies show even more dominance of the three dominant wavelengths and less radiation emitted in other ranges than what is shown in these graphs. What I am seeing is that the percentage of blue light (about 25% or .05 out of .20 in the 3 dominant frequencies) is the same in 6500k and 5000k bulbs - the same amount of blue. The only thing that changes is that green goes from .10 out of .20 to .09 out of .20, and red goes from .05 to .06. More red, less green. This would seem desirable, yes? When you move into the lower kelvin temperatures, the blue becomes a smaller portion of the total light and since blue is the fluoro's bread and butter for growing those compact healthy plants we know and love, this would seem undesirable.
The question I have when it comes to flower is, how good is this 610nm red light for flowering? How much of the growth of buds grown under a mix of 6500k and 3000k lamps is coming from the red and how much from the 440nm blue that is still present even in the 2700k lamps? If the blue is driving growth, how much red does it take to stimulate flowering? It would be interesting to test all 4100k lamps (with a higher percentage of blue and green, and a decent amount of red) vs all 3000k lamps.
Many graphs showing only chlorophyll a and b, or showing individual pigments, seem to treat 610nm red as being nearly useless for plant growth, but other graphs showing overall plant absorption show 610nm red as being in a pretty good part of the red spectrum, or even the very peak. The McCree curve has 610nm at the peak of the graph for "average plant response". It comes from a 1972 academic paper from the journal agricultural meteorology and is often cited by LED manufacturers; it is referenced and linked on the wikipedia page on PAR.

http://plantphys.info/plant_physiology/images/psnpigmentspec.gif
http://www.marigoldlighting.com/wp-content/uploads/2015/03/PAR-Curve.png
http://pinklightaeroponics.net/wp-content/uploads/2014/02/Photosynthesis-Absorption-Spectrum.gif
https://www.google.com/search?q=545nm+wavelength+light&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiu8a25m7TMAhVR4mMKHbEpCJMQ_AUIBygB&biw=1433&bih=748#tbm=isch&q=nm+wavelength+light+plant+absorption&imgrc=LW5TZyGJ4i-8rM:
https://en.wikipedia.org/wiki/Photosynthetically_active_radiation

One thought that came to mind is that the 610nm is slightly higher frequency than the pigment graph's ideal reds that vibrate a little slower. Could it be that the 610nm red slows down slightly as it bounces around in the tent , in the canopy, and in the leaf, thus providing a pretty good usable red spectrum in the process of dissipating into heat? There is some ambiguity about the effectiveness of 610nm red light in driving plant growth, at least for me, because I don't have any experience using all 3000k lamps successfully. Input from anyone with a lot of experience using 2700k and 3000k t5's would be great to illuminate this for me. Do they drive growth on their own or is more blue (higher kelvin temp) better for yields as well as for maintaining healthy plants?

Thoughts?
Nice post ! Good thoughts and questions !

IME GE 4100K are best for overall yield (I've tested several bulbs) I run 18 bulbs in 3, 6 bulb fixtures

tric production is best with 10,000K to 15,000K bulbs I prefer the ATI Coral Plus

I've also tested several WavePoint bulbs, the Ultra Cola bulb is close to the GE 4100K for yield but has a bit of UV

For UV I found the ATI Actinics to be better than the WavePoint Reefwaves

My next test will be with the Agromax line, looking forward to seeing the results of their true UV bulbs
 
I got to thinking about it and assuming that the 610nm red light is close to the 440nm blue in terms of growth and yield, then the lowest percentage of green would theoretically be best, meaning the 3000k lamps take the cake with .07 green out of .24 total or about 29% green light, with 50% red and 21% blue. 3500k is 35% green, 43.5% red, 21.5% blue; 4100k is 38% green, 38% red, 24% blue; 5000k is 45% green, 30% red, 25% blue; 6500k is 50% green, 25% red, 25% blue. So 3000k (or 2700k presumably) is your best source of red as the lowest producer of green light. 4100k gives you nearly as much blue as 5000k and 6500k, but with significantly less green. Unless green light is a lot more important than people think, 5000k should outperform 6500k in veg, and the 4100k could be formidable in veg as well with even less green, 24% instead of 25% blue, and 38% red. I guess a concern there would be if too much red might cause the plants to stretch, but if not, you are getting more usable light with 4100k. Back to flowering, the question there is how much blue do you need? So out of all this I see some mix of 4100k and 3000k/2700k as the ideal for flowering, contingent on the minimum amount of blue being provided by the 4100k's with their awesome 24% blue output, and the rest of the light being provided by 3000k/2700k lamps with their minimal green spectrum. Of course, maybe the 4100k is already at the practical minimum for blue (or green, for that matter) and RM3's plants are approaching the pinnacle of what you can do with standard fluorescent t5's. With 4100k there is kind of a nice symmetry with equal amounts of green and red while only getting a tiny bit less blue than 6500k. So I guess I've decided I'm going switch to 432w of 3000k as a 2 hour "sunrise warmup" and 2 hour "sunset cooldown" to supplement the 8 hours of "noonday sun" of the DE 10K MH and cut down on electricity, including the A/C it will take to cool the DE lamp during the blazing summers here. In a bigger space I would run them together but I will have to give it a shot in this way with my small space. Cheers! Time for a bowl :)
 
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Are these the lamps you are using?

http://bulbsandlighting.com/Ge-46761-54-Watts-T5-F54WT5841ECO-458-_p_126.html


and yeah do you use co2 to get those results?

the ultra growth wave (formerly ultra cola?) looks awesome, that is what I have been looking for to supplement the DE 10k. Covering 620nm to 670nm (not to mention 450nm to 520nm for those using only T5's) seems pretty important if you are going for true full spectrum lighting, thank you for pointing that out!

http://www.wave-point.com/images/LampMain2_enlarge.jpg
http://www.marineandreef.com/WavePoint_Ultra_Growth_Wave_Lamp_45_54W_p/RWP01084.htm?gclid=CJ6vi_rKtcwCFZNhfgodrcAJyA
 
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RM3

Well-Known Member
Are these the lamps you are using?

http://bulbsandlighting.com/Ge-46761-54-Watts-T5-F54WT5841ECO-458-_p_126.html


and yeah do you use co2 to get those results?

the ultra growth wave (formerly ultra cola?) looks awesome, that is what I have been looking for to supplement the DE 10k. Covering 620nm to 670nm (not to mention 450nm to 520nm for those using only T5's) seems pretty important if you are going for true full spectrum lighting, thank you for pointing that out!

http://www.wave-point.com/images/LampMain2_enlarge.jpg
http://www.marineandreef.com/WavePoint_Ultra_Growth_Wave_Lamp_45_54W_p/RWP01084.htm?gclid=CJ6vi_rKtcwCFZNhfgodrcAJyA
yes

no

there is more info in my journal

https://www.rollitup.org/t/the-leprechauns-pot-o-gold.855314/

My grow with the Ultra Cola's
.
0t5.jpg
 
The wavepoint coral wave has some nice lower blues, and then interestingly some infrared as well... maybe I'll try 4 GE 4100k's, 2 coral wave and two ultra growth wave (to go with the 1000w 10k MH - that will bring in some lower blues, higher reds, and infrared. Clorophyll A would be playing a much larger role, and you bring clorophyll F into the fold with the far red/infrared in the coral wave, which I believe is related to photoperiod and flowering response. It hasn't been easy for me to find those spectrums in t5 form.


....I thought of a possible counter-argument to using the 4100k's however, in that maybe getting the most watts into a specific spectrum in any given lamp (bulb) provides greater intensity, and thus greater canopy penetration. So a 2700k/3000k would be putting the max amount of watts into 612nm, for instance...with the 6500k, you're putting max watts (intensity) into 544nm yellow-green, but who's to say that's a bad thing as long as its a low percentage of the total watts in the system. An actinic aquarium lamp will give you the most intense blue in one lamp (I will use the coral wave for the infrared). Actinic lamps also cover from UV to cyan, instead of a narrow bandwidth around 436nm. Tthe ultra growth wave could fill in the far reds admirably while adding cyan, even blue-green and orange. The agromax pure uv could provide the UV in the greatest intensity for a t5.

So with this in mind a different combination would be a ratio of 1 3000k, 1 6500k, 1 coral wave, 1 ultra growth wave, with one or two total of the pure UV (at a greater distance?). This theoretically could give you the best intensity of each spectrum you're including. Plus, I already have 3000k's and 6500k's. Nice.
 
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It would seem the infrared in coral wave does have a real world effect on flowering.

https://www.rollitup.org/t/led-without-leds-my-first-t5-grow.358190/page-71

Here's a quote from another thread on this site from Hyroot on Dec. 1, 2011:

"I did the same thing. the first time i had 2 coral waves and 4 6500k bulbs. I had 2 foot bushy ones that were under a 400 hps then moved under the t5 with 2 corals waves. 2 days later they started flowering so I took one coral wave out and swapped it with the aquablue special from my flower. with one coral they were fine. i had to cut off little buds and topped the ones that I had fimmed. Then a few days ago I put a bunch of clones into soil at the end of the night. Then15 hours later there were buds on 3 different strains. not every one had flowered but quite a few did. i pulled that bulb out and threw in the stock 6500k bulb.

In a 6bulb ,I had 4 6500k bulbs, 1 aquablue special, 1 coral wave. 35% infrared is too much for veg apparently."

I would say throwing vegging plants into flower without a change of light cycle (when they were under HPS before and NOT flowering) is evidence of a pretty strong flowering response to the infrared.
 

Evil-Mobo

Well-Known Member
I think you have convinced me to flower my autos under the T5 and leave my photo for the CMH and then compare...... but my plan was to veg with the T5 and flower with the CMH........

Good looking buds!
 
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