No Pains Gorilla Glue Grow (Free Beans From Herbies) RDWC, LED, CO2

[No Pain]

Thank you, I appreciate that.

don't mention it. Know that you are very welcome

They're handy - flip the top and pour.

it wasn't that they were difficult to use it was the first hydro ferts that I tried. everything didn't always dissolve even with a drill mixer, now granted that was 30 years ago lol

I agree about adding Si and I also use Hydroguard.

Is Si a "supplement"? If so, then I do use supplements but, in the case of Si, I'm adding a chemical that isn't in the ferts rather than adding more of a chemical that's already in the ferts.

It's how we define additives as individuals. I define it as anything that I am adding apart from my base.

Here's my feed sheet for this new res:

"Silica Blast" is the product from Botanicare. I still use the name but make my own Si…mix (I actually typed "suppl…") based on the thread that @farside05 put together about running bloom nutes from drop to chop. That thread and postings and advice from @FelipeBlu were instrumental in my changing from bottled ferts to dry ferts.



Sounds like it works well for you and record keeping is generally a good idea.

records for me are key, what can I say I like the data and it has proven useful.

What strain crapped out at 700?

700ppm was just an example. Take these gg4's they are known to be heavy feeders and well the tips started burning between 700-800 ppm. I attribute that to the consistency of the type of roots in the root zone as fine haired roots allow for more efficient uptake of nutrients so my 700-800 with my root zone could be someone's 1200 with theirs. Along with the Rapid start that aids in that type of development I have custom aerators to make oxygenation of the solution more efficient, I'm aerating below the line of causing nutrients to fall out of solution and that is the key to that. Yes I have made that happen in my endeavors, However I find success through my failures. .

 

[No Pain]

Okay so here we are a day later and what I failed to mention is that I installed a fresh co2 tank and bumper it up to 1200ppm and well these ladies took off to the races. the measurement is on the same cola 24hr later! I actually put a sharpy mark on it today as I couldn't believe it. Picture are worth 1000 words1 Hope everyone is having a fantastic day !

@Wastei Here is the Green Light that I use.

 

[No Pain]

Alrighty I can definitely say that the increase to 1200ppm of co2 is not only worth it but exciting!!! Understand that this is the first grow that I have had a/c a humidifier as well as a dehumidifier in to really dial in the environment as well as adding co2 and its all paying off! The growth has exploded since the increase of co2 it is truly amazing to witness. I will state that I am grateful as well as blessed. Would you believe that in 3 days the control branch / cola has grown 5 1/2 inches!! Remember this is the 4th week of 12/12. I can't wait to see what these things look like this weekend! The is all on a 630-670 ppm solution. I also took a picture of one of the stalks and this is what like 6 weeks from seed! All I can say is Wow. Hope you enjoy the picture porn and that you are having a Fantastic Day!!

here is the start of the first day of 1200 ppm of co2

here is today 3 days later !

now for the rest of the quick pics !

 

[No Pain]

here we are entering 29 days of 12/12 and day 7 of 1200ppm of co2. The ladies have had a res change and ppms reduced by 100 so far looks like pretty even uptake. I can tell you that if I wouldn't have scrogged these ladies and hit them with 1200ppm of co2 they would be about 7 ' tall right now lol. The control branch has doubled in size in the past 6 days! remember the stretch should have been over. I guess they should have a section about but if you give them a good dose of co2 during this stage you bring out titans! The whole canopy is filled with tops and I'm excited for the colas that i see in the future! I had already moved the lights up mid-week and its looking like they could use it again. I may run out of room; However, they are definitely slowing down a bit on their height and starting to put work in on those buds. Either way it's all a blessing to me that I am grateful for. I have dreamt about having a room set up like i have now ever since my aeroflo2 in the mid 90's. Yes, it has taken a minute as everything carries a price tag that is in the room. My advice is to save to set yourself up for success. If you go back and look at my earlier journals when I was just getting back into things and making my own system, you will see that I was in a tent and that was 8 years ago!! Enough jibber jabber, on with the Pics! enjoy and I hope you are all having a Fantastic Day!

 

[gwhunran]

Looking great. Can't wait to see it in mid to late flower.

 

[No Pain]

Looking great. Can't wait to see it in mid to late flower.

Thank you. Me either and I might be a little scared. lol I had what I thought was some light bleaching and i started digging around in the room and it was actually the second plant restricting water to the last two buckets. I was shocked as these are 2 inch pipes lol. So I pulled her root mass or the portion that was wanting to go visit her neighbor back into her domain and needed to do the same with the end lady on the return and she lost a little bit of her roots with that procedure ..pic to follow. So the moral of the story at this stage when changing the res or at least twice a week its make sure their roots are in their own container. One thing that I could have done is prior to putting them in the net is prune their root mass a tad. while I was up there I went ahead and moved the lights to be within min/max recommended distance and well I'm almost out room. lol
here is a picture of the roots I removed from my return line .

 

[SOG001]

WOW very nice grow your plants are looking healthy I'm growing some of Herbies GG#4 in coco I am about 3 weeks in and they are doing ok I started growing back in 2014 but haven't grown for the last two years things have change alot and I have alot to catch up on can't wait to see your girls in flower keep 'em green

 

[No Pain]

WOW very nice grow your plants are looking healthy I'm growing some of Herbies GG#4 in coco I am about 3 weeks in and they are doing ok I started growing back in 2014 but haven't grown for the last two years things have change alot and I have alot to catch up on can't wait to see your girls in flower keep 'em green

Thank you . I haven't done a run since the grand mommy purple that I had to abruptly stop in my signature. Things do change and sometimes rapidly More so in the lighting than anything else. I've done coco well actually tried all the methods and I can say without a doubt that Hydro is what runs through my veins. These next few week are most definitely going to be interesting and with the co2 if they keep stacking it will be interesting by mid week lol . I am most definitely working my butt off to keep these girls on point so they can become their absolute best! I love this Hobby!

 

[gwhunran]

Thank you. Me either and I might be a little scared. lol I had what I thought was some light bleaching and i started digging around in the room and it was actually the second plant restricting water to the last two buckets. I was shocked as these are 2 inch pipes lol. So I pulled her root mass or the portion that was wanting to go visit her neighbor back into her domain and needed to do the same with the end lady on the return and she lost a little bit of her roots with that procedure ..pic to follow. So the moral of the story at this stage when changing the res or at least twice a week its make sure their roots are in their own container. One thing that I could have done is prior to putting them in the net is prune their root mass a tad. while I was up there I went ahead and moved the lights to be within min/max recommended distance and well I'm almost out room. lol
here is a picture of the roots I removed from my return line .

I have to deal with roots following the inflow/drain line from the water pump. I have a maintenance hole cut in my pvc tray cover directly above the inflow and overflow, and it makes things easy. Just have to catch them before they get as long as yours.

 

[No Pain]

Okay so I had mentioned some possible bleaching. First I am going to say that I should have known better as these (good) led fixtures are no joke when it comes to the light intensity that they deliver in comparison to hid's. I feel we are still in the transitional learning curve over all much like when the industry moved from fluorescents to HID lamps. With that said there is much to learn and more that we focus on as growers now ... ppfd, VPD and a new on the list and I Thank @Delps8 for my new addition which is DLI and it is very important as when it comes to lighting it tells you how hard you are pushing your plants as well as when you are just wasting light . Yes I said wasting light, Yes it is very possible. For those of you that are new to the term DLI here is its definition and within that you will understand why there is a focus on ppfd when it comes to lights and there advertisement.

DLI- Daily light integral (DLI) is the amount of PAR received each day as a function of light intensity (instantaneous light: μmol·m-2·s-1) and duration (day). It is expressed as moles of light (mol) per square meter (m-2) per day (d-1), or: mol·m-2·d-1 (moles per day). The DLI concept is like a rain gauge.

For Cannabis Different strains have different DLI stress points, and while the range is wide, virtually all strains can handle somewhere between 40-50 DLI..... some would argue like myself with elevated co2 1200-1500 they can use 60 DLI
here is a chart from a random site and there recommendations

now why is this important ..well anything about the maximum dli for your given situation is just a waste of light and electricity. Meaning that once your plant receives its maximum everything else just rolls off. Sort of like a pot of soil once it reaches its maximum saturation point any water that comes after that just rolls off and is of no use.

so now that you have a little bit of a foundation. Seeing the potential bleaching and DLI hitting me in the Face continuously in @Delps8 's journal. I looked it up and then took my hydrofarm quantum par meter and took a measurement at the top of the branch with the bleaching that I saw ..well it was at 3000 ppfd!!! which gave me a dli of . wait for it and look at the chart as well as me stating with correct co2 level I feel 60 is achievable. My DLI was 129.6 !!

So what does that mean? It means that the plant achieved its maximum growth rate and absorbed as much photos as it could for an entire day within 6 hrs of my 12 hrs light cycle and the remaining 6 hours the lights did nothing for it !!!

That my friends is why we should all understand the term DLI as well as know what it is for our plants! Again Thank you and my plants thank you @Delps8 for you being you and posting the details that you do.

Thank goodness I purchased the dimmer options for my lamps. lol I currently have the DLI dialed in slightly under optimal to give my lady some recovery time. Here is a picture of what it looked like prior to the change and I'm tracking it daily now.

Its also important to note that to much can also cause burning on the edges of the leaves much like when you are having an overfertilization problem ..that information came from an hour long video I watched yesterday on DLI ..so if you are running low ec/ppm/tds and you're starting to see the edges running down the leaves burn ..you need to ask yourself. What is my DLI.

 

[No Pain]

Here we are at the Start of Day 35 of flower. I have moved the lights all the way up and used the dimmer to balance out the ppfd across the canopy average is 1100. I Believe what I thought was bleaching due to the lights was actually a slight cal mag deficiency. Hadn't been adding any this entire grow and well it is known that with the use of led lamp that they use a bit more and I was really pushing them with the co2 and light intensity and they were/are most definitely responding. We shall see here in the next few days ads they have just had a res change with said additive at 1ml per gallon. All in all they are doing fantastic. They are getting pretty woodsy and starting to focus mainly on flower growth the past 2 days. That is a yard stick in the picture and I show that the base is even with the netting. Also frost is amoung us !! I'm excited! Hope everyone is having a fantastic day! On with the Pics!

 

[Delps8]

If those plants looked any happier, they'd have to get a room.

Oh wait…


On a more serious note, 1100µmols in CO2 is well away from "pushing" cannabis. Check out the attached paper (the "Chandra" paper). Bugbee recommends 1200 and 1200 and has repeatedly stated that, in enhanced CO2, they have not found a DLI limit for cannabis. They stopped at 2000µmol.

The light saturation point for ambient CO2 is 800-1kµmol and I prefer to run my grows right at the 1k± level and the biggest issue I've had is that I've had to burn the crop a couple of grams at a time.

From the Chandra paper.

That deals with, among other things, net Photosynthesis and, yes, the curve rolls off.

That issue is addressed in the Frontiers paper. From the Conclusions:

"We have shown an immense plasticity for cannabis to respond to increasing LI; in terms of morphology, physiology (over time), and yield. The temporal dynamics in cannabis leaf acclimations to LI have also been explored, addressing some knowledge- gaps in relating cannabis photosynthesis to yield. The results also indicate that the relationship between LI and cannabis yield does not saturate within the practical limits of LI used in indoor production. Increasing LI also increased harvest index and the size and density of the apical inflorescence; both markers for increasing quality. However, there were no and minor LI treatment effects on potency of cannabinoids and terpenes, respectively. This means that growers may be able to vastly increase yields by increasing LI but maintain a relatively consistent secondary metabolite profile in their marketable products. " (emphasis mine).

"Turn it up to 11!"

 

[No Pain]

Thank you.I know what you mean. If you look back my dli was around 129!! When i noticed what I though was bleaching. I gave them a little break for about a week . Dr.Bruce Bugbee states that cannabis with ideal conditions can handle a dli of 70 ! I'm working on cranking it up after I see If the extra cal mag works. I feel that it will.

Side note ...full sun at high noon is around 2000 ppfd

 

[Delps8]

Thank you.I know what you mean. If you look back my dli was around 129!! When i noticed what I though was bleaching. I gave them a little break for about a week . Dr.Bruce Bugbee states that cannabis with ideal conditions can handle a dli of 70 ! I'm working on cranking it up after I see If the extra cal mag works. I feel that it will.

Side note ...full sun at high noon is around 2000 ppfd

Nothing wrong with a DLI of 129. The max PPFD of the sun varies significantly, according to atmospheric conditions, latitude, time of day, and day of the year. On June 21, 2022, I recorded > 2200 mols here in SoCal. The air quality was good and skies were clear. I tested it with my Apogee and, for the hell of it, ran Photone, too.

Photone, of course, wobbled all over the place but the Apogee came in at a fairly steady value. At that time, I ran Apogee's Clear Sky app on my iPhone and it told me that my meter was reading about 2% low.

Cannabis will easily handle 70mols. I run that in veg as a matter of course. Check my grow journals. The light data for my current grow is shown below, up to flip. That's in ambient CO2 which, according to the Inkbird CO2 meter I got last year, runs about 500.

It's just not a big deal to the plant but growers, by and large, have little understanding that they can get a bigger crop just by turning up the dial.

I get that - I followed conventional wisdom and didn't question the recommendations of various cannabis sites for my first couple of grows. Even after I'd learned a metric shit ton about light levels, it wasn't until June of '22 that I got my head out of my ass and made the switch.

It's great to get all that additional growth but, when make the switch, you're going to increase photosynthesis significantly. More photons ==> more photosynthesis ==> more food for the plants but also > transpiration. With increase transpiration, be watchful for tip burn. That's what got me when I went to flower.

My grow is now at 0.9 EC (450/500). IIRC, you, too, are at a low PPM like that but, with the high level of photosynthesis and respiration, that's "just right".

When you bump your PPFD, keep an eye out for that and, if need be, drop some PPM.

Bugbee has addressed light bleaching and his research has found that it happens when there is a lot of far red in the spectrum. The plants were exposed to a spectrum that had a high percentage of far red in veg and the bleaching was visible when the plants flowered. That was in an interview, not in one of his teaching vids.

Oh, re. high PPFD and CO2 - "the" paper about photosynthesis and high PPFD was released in 2008 (the "Chandra" paper because Suman Chandra was the primary author). One of the graphics from the document is shown below. It shows that the photosynthesis curve starts to roll off at about 500PPFD and the curve is widely taken to indicate that there's not a lot of value in going much higher than that.

I didn't question that attitude at first because it fits in so well with the "600 PPFD in veg" mindset. What was always in the back of my mind was "But I'm not harvesting net photosynthesis".

It took me a while to move past that and it came in the form of the Frontiers paper (attached) .

From the Discussion:

"Cannabis Inflorescence Yield Is Proportional to Light Intensity
It was predicted that cannabis yield would exhibit a saturating response to increasing LI, thereby signifying an optimum LI range for indoor cannabis production. However, the yield results of this trial demonstrated cannabis’ immense plasticity for exploiting the incident lighting environment by efficiently increasing marketable biomass up to extremely high—for indoor production—LIs (Figure 7A). Even under ambient CO2 , the linear increases in yield indicated that the availability of PAR photons was still limiting whole-canopy photosynthesis at APPFD levels as high as ≈1,800 μmol·m−2·s−1 (i.e., DLI ≈78 mol·m−2 ·d−1 )."

The study directly addresses the Chandra study and provides a rationale as to why it has a weak basis for predicting yield.

This table is from the paper:

All of this is happening in ambient CO2. Since you're running CO2, the numbers will be different and even better.

In addition to the great info on lighting, when I read the paper yesterday AM, I realized something that I'd completely missed — the paper reveals that there was no difference in yield or quality metrics between plant that were topped and plants that were not topped. I have never believed that topping has a negative impact on a cannabis plant and, at least in this case, there results support my contention.

 

[No Pain]

Nothing wrong with a DLI of 129. The max PPFD of the sun varies significantly, according to atmospheric conditions, latitude, time of day, and day of the year. On June 21, 2022, I recorded > 2200 mols here in SoCal. The air quality was good and skies were clear. I tested it with my Apogee and, for the hell of it, ran Photone, too.

In one of Bugbees latest videos about his new light meter that measures the full spectrum and is handheld, it also displays a true graph of the wave lengths ! Its the umm ms-100 I believe .he stated in that video as well as in some interviews that the sun at its brightest is around 2000 ppfd on average at high noon. In a couple of interviews he did state that a DLI of 60 with co2 was around the area of max gain per energy and dollar spent but that cannabis is a racecar and could even handle 70 DLI possibly even more.

Photone, of course, wobbled all over the place but the Apogee came in at a fairly steady value. At that time, I ran Apogee's Clear Sky app on my iPhone and it told me that my meter was reading about 2% low.

Cannabis will easily handle 70mols. I run that in veg as a matter of course. Check my grow journals. The light data for my current grow is shown below, up to flip. That's in ambient CO2 which, according to the Inkbird CO2 meter I got last year, runs about 500.

I will Look for the video about 60 being the highest with supplemented co2 and all other parameters being correct. I have never tried their phone app . I will have to look into it and compare it to my hand held.

It's just not a big deal to the plant but growers, by and large, have little understanding that they can get a bigger crop just by turning up the dial.

Yes I agree that every grower and particularly indoor growers should have an understanding of this. It may sound like its complicated but to me if you can mix nutrients and test ph you can absorb this information with ease and greatly benefit from it.

I get that - I followed conventional wisdom and didn't question the recommendations of various cannabis sites for my first couple of grows. Even after I'd learned a metric shit ton about light levels, it wasn't until June of '22 that I got my head out of my ass and made the switch.

My initial wisdom came from books with no online support. lol But I do know what you mean .

It's great to get all that additional growth but, when make the switch, you're going to increase photosynthesis significantly. More photons ==> more photosynthesis ==> more food for the plants but also > transpiration. With increase transpiration, be watchful for tip burn. That's what got me when I went to flower.

I have just become aware that some tip burn can be cause by a calcium deficiency ..I'm still looking into it .

My grow is now at 0.9 EC (450/500). IIRC, you, too, are at a low PPM like that but, with the high level of photosynthesis and respiration, that's "just right".

When you bump your PPFD, keep an eye out for that and, if need be, drop some PPM.

I have found my sweet spot it seems to be an ec of .9 balance uptake and pretty stable ph..I switch to e/c as its more universal as you have a 500 and a 700 scale when it comes to tds/ppm

I do keep a good eye on it .

Bugbee has addressed light bleaching and his research has found that it happens when there is a lot of far red in the spectrum. The plants were exposed to a spectrum that had a high percentage of far red in veg and the bleaching was visible when the plants flowered. That was in an interview, not in one of his teaching vids.

Yes it was an interview and he stated that the bleaching was white and did not affect the plant at all if I remember correctly. I do know my lamps have some far red as in the 750nm range

Oh, re. high PPFD and CO2 - "the" paper about photosynthesis and high PPFD was released in 2008 (the "Chandra" paper because Suman Chandra was the primary author). One of the graphics from the document is shown below. It shows that the photosynthesis curve starts to roll off at about 500PPFD and the curve is widely taken to indicate that there's not a lot of value in going much higher than that.

I didn't question that attitude at first because it fits in so well with the "600 PPFD in veg" mindset. What was always in the back of my mind was "But I'm not harvesting net photosynthesis".

It took me a while to move past that and it came in the form of the Frontiers paper (attached) .

From the Discussion:

"Cannabis Inflorescence Yield Is Proportional to Light Intensity
It was predicted that cannabis yield would exhibit a saturating response to increasing LI, thereby signifying an optimum LI range for indoor cannabis production. However, the yield results of this trial demonstrated cannabis’ immense plasticity for exploiting the incident lighting environment by efficiently increasing marketable biomass up to extremely high—for indoor production—LIs (Figure 7A). Even under ambient CO2 , the linear increases in yield indicated that the availability of PAR photons was still limiting whole-canopy photosynthesis at APPFD levels as high as ≈1,800 μmol·m−2·s−1 (i.e., DLI ≈78 mol·m−2 ·d−1 )."

The study directly addresses the Chandra study and provides a rationale as to why it has a weak basis for predicting yield.

This table is from the paper:

All of this is happening in ambient CO2. Since you're running CO2, the numbers will be different and even better.

oh yes I can definitely see the difference that the co2 has made. I had always run the lights within a specific hieght from the canopy and well the results using co2 really blew me away !

In addition to the great info on lighting, when I read the paper yesterday AM, I realized something that I'd completely missed — the paper reveals that there was no difference in yield or quality metrics between plant that were topped and plants that were not topped. I have never believed that topping has a negative impact on a cannabis plant and, at least in this case, there results support my contention.

Yes he talked about that in an interview I watched yesterday. However he didn't mention plant height and I do not believe that he was referring to a scrog. He did state that the results surprised him he also talked about defoliation a tad as well in this interview.

 

[Delps8]

In one of Bugbees latest videos about his new light meter that measures the full spectrum and is handheld, it also displays a true graph of the wave lengths ! Its the umm ms-100 I believe .he stated in that video as well as in some interviews that the sun at its brightest is around 2000 ppfd on average at high noon.

That's the spectroradiometer that analyses the spectrum of a light source. Very interesting device if you're in that market. That would be a consultant or a grower in a large facility, perhaps? The only time I deal with a change in the spectrum is in very early veg when I run my Vipar XS 1500 + a blue LED. I run that for "a few days" and I use the blue LED for "more shortness". To get an idea of my spectrum, I shut off the XS1500 and take a reading of just the LED. I like to get about 50µmol from the puck.

In a couple of interviews he did state that a DLI of 60 with co2 was around the area of max gain per energy and dollar spent but that cannabis is a racecar and could even handle 70 DLI possibly even more.

Did he allude to anything published? We know the yield curve starts to rolloff pretty low but we're not harvesting net P and the study, Chandra, derived its data from capturing data from leaves in a grow chamber about the size of two shoe boxes.

That approach is addressed in the Frontiers paper and, as that paper demonstrated, crop yield increased in an almost linear manner up to 1800µmol in ambient CO2.

The other issue with putting dollar numbers around a grow is that becomes a cost accounting issue, which is an entire career in itself. The only study I've seen on is the paper I've attached and it raises the appropriate points (no surprise). Overall, cannabis is an extremely high value crop so the marginal increase in revenue is, generally speaking, so high that it far exceeds the marginal increase in cost.

Anticipated yield values are one input into the calculations but, after that, it's all about fixed and variable costs versus estimated changes in revenue. Some situations are very simple but when you get into cost accounting, it can get exceeding complex.

I will Look for the video about 60 being the highest with supplemented co2 and all other parameters being correct. I have never tried their phone app . I will have to look into it and compare it to my hand held.

Good luck with that. I would not use the values from the app unless the app + phone was calibrated against a known good source. Don't forget to use the diffuser and I've read that they now specify the paper to use. The first time I tested it, it was called "Korona" at the time, they didn't specify what paper to use. I sent them test results using 20, 22, and 24# paper and I think they caught on after that.

Yes I agree that every grower and particularly indoor growers should have an understanding of this. It may sound like its complicated but to me if you can mix nutrients and test ph you can absorb this information with ease and greatly benefit from it.

Agree 100%. The more grows I see, the more the KISS approach makes sense. "It's a plant - feed it, water it, and it's do fine." I've modified that to include "and stop cutting off all the leaves".

I have just become aware that some tip burn can be cause by a calcium deficiency ..I'm still looking into it .

Because it's immobile?

I have found my sweet spot it seems to be an ec of .9 balance uptake and pretty stable ph..I switch to e/c as its more universal as you have a 500 and a 700 scale when it comes to tds/ppm

I do keep a good eye on it .

Agree - EC is the actual value that's being measured. I use the 500 scale and use the annotation "N/500" to indicate that. My reason for not using EC is twofold:

1. it's constantly dropping so the rate of change is more important than the actual value; EC represents 50/500 PPM
2. my meter only does EC in increments of 0.1 which means my PPM can drop from 450 to 430 but that is still EC 0.9. For my 26 gallon res, that's a significant change in the amount of chemicals in my res but I won't know it if I'm not using PPM. On the other hand, EC in a 5 gallon bucket is probably more appropriate because, with only 4± gallons of nutes, the changes, however expressed, will be much faster.

Don't know if this came in over your transom but the rate of uptake of the chemicals in a res is highly influenced by just a few chemicals. Check page two of the attached paper. O

Yes it was an interview and he stated that the bleaching was white and did not affect the plant at all if I remember correctly. I do know my lamps have some far red as in the 750nm range

Yes, there were bleached and the downside was "curb appeal".

My notes from that part of the video (42:42)
Higher light bleaching at the top part of teh flower. The amount of read 600µmols for 16 hours cultivar dependent. No impact on yield but looks bad. Bugbee thinks it happens when it's small. It doesn't happen in any other crop.
High fraction of red and high intensity.
One speaker postulated is was from heavily bred genetics
Reduce red and then bring it back in.

oh yes I can definitely see the difference that the co2 has made. I had always run the lights within a specific hieght from the canopy and well the results using co2 really blew me away !

I can imagine! The numbers that I've seen are 25% and 30%. That's pretty friggin' amazing.

Yes he talked about that in an interview I watched yesterday. However he didn't mention plant height and I do not believe that he was referring to a scrog. He did state that the results surprised him he also talked about defoliation a tad as well in this interview.

AFAIK, Bugbee has always been a "remove dead and heavily senesced and blocking air flow". Did he change his perspective?

I follow that guideline but I also removed thin stems that won't result in harvestable flower. That goes along with my "Leave the damn thing alone!" but then I fight my way through the attached document and wonder if I should change my approach. I'd guess I've read through that document…four times now and it's a slog. I need to (gasp) print it out so I can see the descriptions of the pruning techniques as I read the rest of the document.

If you dig into it, lemme know what you think, would you?

 

[Delps8]

I made my way through this video this morning.

It was interesting to see how much green light is used for photosynthesis. One very interesting statement ( I don't have the timestamp but it's in the Q&A)

From my notes:
"I talk a lot about P and I could give a talk about why, in many cases, it is a really poor indicator of plant growth. You cannot correlate, in many cases, high growth with high P rate. the most important factor being the size of the canopy.
You can manipulate the light spectrum to get plants to develop a lot of canopy allowing it intercept more light and they will grow faster as a results and that effect on the plant morphology on plant growth is probably more important."

A good sign, and one that distinguishes a scientist from a non-scientist, is the almost complete absence of absolute statements. It's a tell.

It would be interesting to know the exceptions and, I'd wager that cannabis is one of them. I'd make that bet based on statements by the authors of the Frontiers paper.

Overall, though, his point is well taken because a photon hitting the floor of the tent is a photon that the plant can't use for P.

 

[No Pain]

That's the spectroradiometer that analyses the spectrum of a light source. Very interesting device if you're in that market. That would be a consultant or a grower in a large facility, perhaps? The only time I deal with a change in the spectrum is in very early veg when I run my Vipar XS 1500 + a blue LED. I run that for "a few days" and I use the blue LED for "more shortness". To get an idea of my spectrum, I shut off the XS1500 and take a reading of just the LED. I like to get about 50µmol from the puck.

Yeah I though the device was very interesting and well with a 1600.00 price tag it wont be one of my toys. lol

Did he allude to anything published? We know the yield curve starts to rolloff pretty low but we're not harvesting net P and the study, Chandra, derived its data from capturing data from leaves in a grow chamber about the size of two shoe boxes.

That approach is addressed in the Frontiers paper and, as that paper demonstrated, crop yield increased in an almost linear manner up to 1800µmol in ambient CO2.

The other issue with putting dollar numbers around a grow is that becomes a cost accounting issue, which is an entire career in itself. The only study I've seen on is the paper I've attached and it raises the appropriate points (no surprise). Overall, cannabis is an extremely high value crop so the marginal increase in revenue is, generally speaking, so high that it far exceeds the marginal increase in cost.

Anticipated yield values are one input into the calculations but, after that, it's all about fixed and variable costs versus estimated changes in revenue. Some situations are very simple but when you get into cost accounting, it can get exceeding complex.

I would have to watch it again as what stuck in my head was 60dli with co2 was the best bang for the buck. IM not necessarily putting dollars to it but more so focused on the highest peak with the greatest efficiency and I always tend to push it a tad over that. i.e why feed my plants 1200 ppm when i can see pretty close to the same results at 700ppm. Its not what it costs me to give it 1200ppm is that it seems in efficient to give it more when the results from it do not run parallel with the increase in nutrition .

Good luck with that. I would not use the values from the app unless the app + phone was calibrated against a known good source. Don't forget to use the diffuser and I've read that they now specify the paper to use. The first time I tested it, it was called "Korona" at the time, they didn't specify what paper to use. I sent them test results using 20, 22, and 24# paper and I think they caught on after that.

I use my light meter to measure my light intensity . I just mentioned the app as I had never looked at it and well Just to mess around I would like to see how big a difference it is. As many people do use a phone app and I feel there is a large error in it but I have no Comparisions.

Agree 100%. The more grows I see, the more the KISS approach makes sense. "It's a plant - feed it, water it, and it's do fine." I've modified that to include "and stop cutting off all the leaves".

I will still pluck at day 21 of 12/12 muhaha :

Because it's immobile?

yes that is correct and Plants under Led ted to use/require a tad more

Agree - EC is the actual value that's being measured. I use the 500 scale and use the annotation "N/500" to indicate that. My reason for not using EC is twofold:

1. it's constantly dropping so the rate of change is more important than the actual value; EC represents 50/500 PPM
2. my meter only does EC in increments of 0.1 which means my PPM can drop from 450 to 430 but that is still EC 0.9. For my 26 gallon res, that's a significant change in the amount of chemicals in my res but I won't know it if I'm not using PPM. On the other hand, EC in a 5 gallon bucket is probably more appropriate because, with only 4± gallons of nutes, the changes, however expressed, will be much faster.

Oh yes ppm is most definitely easier to fine tune things and sometimes i forget to mention the scale and if i put things in terms of ec I don't have to. lol

Don't know if this came in over your transom but the rate of uptake of the chemicals in a res is highly influenced by just a few chemicals. Check page two of the attached paper. O

I will most definitely check out the paper

Yes, there were bleached and the downside was "curb appeal".

My notes from that part of the video (42:42)
Higher light bleaching at the top part of teh flower. The amount of read 600µmols for 16 hours cultivar dependent. No impact on yield but looks bad. Bugbee thinks it happens when it's small. It doesn't happen in any other crop.
High fraction of red and high intensity.
One speaker postulated is was from heavily bred genetics
Reduce red and then bring it back in.

I do feel that genetics plays a large roll in that .

I can imagine! The numbers that I've seen are 25% and 30%. That's pretty friggin' amazing

yes it is ..now look at it this way ..use of co2 has always been known to increase yields by 20-30% and there was never any mention of DLI or VPD so imagine what the % increase has the potential to be with those dialed in .

.


AFAIK, Bugbee has always been a "remove dead and heavily senesced and blocking air flow". Did he change his perspective?

It was a study that one of his students did in comparing topping a plant to not topping a plant . He still had the same stance as far as removing old leaves and those that block airflow at the bottom of the plant / Loli popping

I follow that guideline but I also removed thin stems that won't result in harvestable flower. That goes along with my "Leave the damn thing alone!" but then I fight my way through the attached document and wonder if I should change my approach. I'd guess I've read through that document…four times now and it's a slog. I need to (gasp) print it out so I can see the descriptions of the pruning techniques as I read the rest of the document.

If you dig into it, lemme know what you think, would you?

I will dig into it and tell you what my thoughts are. I have saved all three. Thank you for posting them.

 

[Delps8]

Yeah I though the device was very interesting and well with a 1600.00 price tag it wont be one of my toys. lol

Same here.

I would have to watch it again as what stuck in my head was 60dli with co2 was the best bang for the buck. IM not necessarily putting dollars to it but more so focused on the highest peak with the greatest efficiency and I always tend to push it a tad over that. i.e why feed my plants 1200 ppm when i can see pretty close to the same results at 700ppm. Its not what it costs me to give it 1200ppm is that it seems in efficient to give it more when the results from it do not run parallel with the increase in nutrition .

60 DLI in flower = 1500µmol and that's that just happens to be where the P curve goes negative in Chandra, shown here.
But that's photosynthesis, not yield.

I use my light meter to measure my light intensity . I just mentioned the app as I had never looked at it and well Just to mess around I would like to see how big a difference it is. As many people do use a phone app and I feel there is a large error in it but I have no Comparisions.

I'd go with your PAR meter. Thinking of which, Apogee has released an iPhone app that you can use to check your PAR meter. It's called "Clear Sky Calculator". If you've got an iPhone, snag a copy and take it for a spin.

I will still pluck at day 21 of 12/12 muhaha :

yes that is correct and Plants under Led ted to use/require a tad more

Oh yes ppm is most definitely easier to fine tune things and sometimes i forget to mention the scale and if i put things in terms of ec I don't have to. lol

Understood.

I will most definitely check out the paper

I do feel that genetics plays a large roll in that .

Some cultivars can't go > 700 so, it does vary. That's a given. The issue is that, once you get away from the Chandra net P focus, the results are really friggin' amazing. One of the authors of the Frontiers paper is name Zheng and he just happens to have been a student under Bugbee. Small world, eh?

yes it is ..now look at it this way ..use of co2 has always been known to increase yields by 20-30% and there was never any mention of DLI or VPD so imagine what the % increase has the potential to be with those dialed in .

Yup, get all those ducks in a row and pretty soon you have a lot of flockin' weed!

It was a study that one of his students did in comparing topping a plant to not topping a plant . He still had the same stance as far as removing old leaves and those that block airflow at the bottom of the plant / Loli popping

I will dig into it and tell you what my thoughts are. I have saved all three. Thank you for posting them.

You're welcome. I've posted those in a few other threads, as well as on another cannabis site and, on the other site, they've been well received. The toughest one to get through was the paper on pruning/defol. Lollipoping had one of the worst outcomes (there were a few that were worse) but the technique with the best outcome was referred to as "double defoliation", IIRC, but I wasn't able to get a good sense of what that entailed. Also, I'm not sure just how much better the double defol was than, say, the control.

And there's always the argument that if you feed it and water it, just got so much weed anyway so why bother? That's sorta where I am but if there's a significant improvement in yield, say 10%+, I'd seriously consider it.

 

[No Pain]

okay here we are at the middle of day 42 of 12/12. The ladies have had a res change and are at 430ppm on a 500 scale and cruising at a ph of 5.7. everything is looking good. I have included an upskirt shot to show the light penetration through that canopy that looks super dense as well a one of a stalk this are thick ladies . On with the pic! I hope everyone is having a fantastic day !!!

side note @Delps8 ..I have read the nutrient paper 2 more to go ..Good stuff I will post about it later. Thank you again for sharing.