chiesesganja
Well-known member
depends on strains too.... i feel sativa more near indica more far
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LED feed demands
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oldschoolnitro
Member
Higher room temps is Key to nutrient absorption under LED
Higher room temps is Key to nutrient absorption under LED
With LED having a higher room temperature is critical..when I first went over to LED I had all sorts of nutrient trouble that I couldn't solve... I did some research and found that LED needed higher room temps due to lack of UV radiation..So I bumped my room temp to 85 and everything started to come together. I just use plain old 3 part GH with Calmag in Coco, EC 2.0 and i'm killing it ..
Higher room temps is Key to nutrient absorption under LED
With LED having a higher room temperature is critical..when I first went over to LED I had all sorts of nutrient trouble that I couldn't solve... I did some research and found that LED needed higher room temps due to lack of UV radiation..So I bumped my room temp to 85 and everything started to come together. I just use plain old 3 part GH with Calmag in Coco, EC 2.0 and i'm killing it ..
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Grapefruitroop
Active member
Exxxxxxcellent!
Beautiful job!
Calmag till the end or you lower a little bit in the end o flowerin?
Beautiful job!Calmag till the end or you lower a little bit in the end o flowerin?
Mudraya
Active member
Really enjoyable thread but this may just be the key to the kingdom? Have you increased feed the aforementioned 40% or at all? (Edit, I see your EC there...I mean is it higher than it was before?) No other changes other than upping temps?
Just got a new toy and thinking I may feel like a newb soon, which can be fun sometimes.
Just got a new toy and thinking I may feel like a newb soon, which can be fun sometimes.
I am also experiencing problems with my LEDS but only the white leds like fluence and sf4000. The fluence giving me the most problems (330watts).
The blurple ones like viparspectra don't give me any issues at all.
Here is a question for the more nowledgable members.
I have had my sf4000 for 3 weeks. The first 2 weeks in the motherroom, everythign went perfect. Just beautiful healthy plants.
There was also a blurple led in that room. I take away the blurple so there is only white light and 2 days later plants start freaking out with mg and ca deficiencies. Can someone give a logical explanation for this? I am trying to understand. So total ppfd goes down and spectrum changes due to no more blurple side lighting
The blurple ones like viparspectra don't give me any issues at all.
Here is a question for the more nowledgable members.
I have had my sf4000 for 3 weeks. The first 2 weeks in the motherroom, everythign went perfect. Just beautiful healthy plants.
There was also a blurple led in that room. I take away the blurple so there is only white light and 2 days later plants start freaking out with mg and ca deficiencies. Can someone give a logical explanation for this? I am trying to understand. So total ppfd goes down and spectrum changes due to no more blurple side lighting
SuperBadGrower
Active member
"Correlation is not causation" could apply. If you give too much light you won't see symptoms immediately. Maybe the change in spectrum has also altered how you see the plant. A deficiency can look worse or better than it really is under a different spectrum.
Remember that ~55w of modern white leds already matches ~100w of purple in light output. (It's easier to grow healthy plants in low but adequate light conditions)
A thing you could look at is the B:R ratio, it being much higher on the SF. it actually has more blue than anything in the spectrum. Blue light is known to inhibit cell elongation, (stem) purpling. I suspect that some growing problems may have to do with high ratios blue light, but that's just speculation.
I don't want to speak outside of my experience. I have never used LEDs with such a high blue ratio. Up to 3500K or 4000K the blue is significantly lower.
Or maybe increase the feed. I am not afraid to feed 2+ EC in veg, real good results (note: coco, not dwc).
Just some thoughts.
Remember that ~55w of modern white leds already matches ~100w of purple in light output. (It's easier to grow healthy plants in low but adequate light conditions)
A thing you could look at is the B:R ratio, it being much higher on the SF. it actually has more blue than anything in the spectrum. Blue light is known to inhibit cell elongation, (stem) purpling. I suspect that some growing problems may have to do with high ratios blue light, but that's just speculation.
I don't want to speak outside of my experience. I have never used LEDs with such a high blue ratio. Up to 3500K or 4000K the blue is significantly lower.
Or maybe increase the feed. I am not afraid to feed 2+ EC in veg, real good results (note: coco, not dwc).
Just some thoughts.
SuperBadGrower
Active member
Here is something. same genetics, both vegging in my high intensity veg (that's about 400-500 ppfd) with nothing but 3000K
In: 1.9 EC,
Runoff: 3 EC
Runoff: 1.1 EC
if you wonder why are the values so different, because I'm too busy to care. Now if you forget about numbers, what do you think, which plant would you rather grow?
If a plant looks like shit I'll hit it with 3 EC or more, depending how little I care about the plant. actually that's what I did with the one on the left. From then on feed the regular amount. it usually greens up and the runoff EC steadily drops back to normal over time.
Honestly, this plant and some similar ones, if I feed under 1.6 EC I'll always be having deficiencies under such intense light, as most people are using with LEDs now. You will always see the interveinal chlorosis until youput it under 200 µmol or less.
If you look at application rates for agriculture nutrients you'll see they have regimens for occasional or continuous feeding.You can think of it like that. People are so scared of high EC in medium. look up what EC your tomatoes and cucumbers are grown in, and weep.
I'm not saying weed is the same but I am always pushing the salinity threshold,,, why, cause high EC always correlates with high Brix. but that's not a discussion for this thread
Of course 1 EC of formula X is not equal to 1 EC of formula Y. just some thoughts.
So like I always say it's a complicated interaction, I guess. The plant on the right might make you say, light burn! But if you gave it more food it might be able to handle it. Many plants don't like the high intensity during veg at all.
In: 1.9 EC,
Runoff: 3 EC
Runoff: 1.1 EC
if you wonder why are the values so different, because I'm too busy to care. Now if you forget about numbers, what do you think, which plant would you rather grow?
If a plant looks like shit I'll hit it with 3 EC or more, depending how little I care about the plant. actually that's what I did with the one on the left. From then on feed the regular amount. it usually greens up and the runoff EC steadily drops back to normal over time.
Honestly, this plant and some similar ones, if I feed under 1.6 EC I'll always be having deficiencies under such intense light, as most people are using with LEDs now. You will always see the interveinal chlorosis until youput it under 200 µmol or less.
If you look at application rates for agriculture nutrients you'll see they have regimens for occasional or continuous feeding.You can think of it like that. People are so scared of high EC in medium. look up what EC your tomatoes and cucumbers are grown in, and weep.
I'm not saying weed is the same but I am always pushing the salinity threshold,,, why, cause high EC always correlates with high Brix. but that's not a discussion for this thread
Of course 1 EC of formula X is not equal to 1 EC of formula Y. just some thoughts.
So like I always say it's a complicated interaction, I guess. The plant on the right might make you say, light burn! But if you gave it more food it might be able to handle it. Many plants don't like the high intensity during veg at all.
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SuperBadGrower
Active member
For reference, here is a plant I do care about, stable runoff around 1.9 EC always
Same light intensity
I believe the shine on the leaf is the indication of high BRIX. If the leaves don't shine there's not enough food IME
edit: ok, final thought, because I enjoy the topic and discussion. If you are hydroponics, i.e. coco and beyond, learn to use hydrobuddy and educate yourself about nutrient ppms. Even if I fed 200% strength of my A&B (3 EC) I'm still only at like 20ppm Mg. it's just that low in Mg. You can find all kinds of target ppms for elements in plants which I mentioned such as cucumbers, tomato, pepper. Most people reach for the magnesium sulfate, but I will offer you an alternative: Magnesium nitrate. You can make your own perfect calmag, using hydrobuddy. The ingredients are Calcium nitrate, magnesium nitrate and (optionally) an iron chelate like DTPA.
If you add normal calmag products on top of some A&Bs calcium can get unnecessarily high.
https://cropnuts.helpscoutdocs.com/article/826-iron-fertilisation
Same light intensity
I believe the shine on the leaf is the indication of high BRIX. If the leaves don't shine there's not enough food IME
edit: ok, final thought, because I enjoy the topic and discussion. If you are hydroponics, i.e. coco and beyond, learn to use hydrobuddy and educate yourself about nutrient ppms. Even if I fed 200% strength of my A&B (3 EC) I'm still only at like 20ppm Mg. it's just that low in Mg. You can find all kinds of target ppms for elements in plants which I mentioned such as cucumbers, tomato, pepper. Most people reach for the magnesium sulfate, but I will offer you an alternative: Magnesium nitrate. You can make your own perfect calmag, using hydrobuddy. The ingredients are Calcium nitrate, magnesium nitrate and (optionally) an iron chelate like DTPA.
If you add normal calmag products on top of some A&Bs calcium can get unnecessarily high.
https://cropnuts.helpscoutdocs.com/article/826-iron-fertilisation
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SuperBadGrower
Active member
Now look at this new growth, near perfection. That plant looked handicapped just a few days ago
1.9 EC
Perky again
Gotta make em shine
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Grapefruitroop
Active member
Thats another important point! Majority of nutrients formulas are not rich enough in Mg to support such a boosted photosyntesys..
Yes Magnesium Nitrate is gold
also
1g of Epsom salt x Gal adds roughly 25ppmMg and 30ppm S
SuperBadGrower
Active member
Yep
Here are some random hydro A&Bs anyone can buy today
(Always substract 63 Ca, it is my tap water. ppms based obviously on what the manufacturer reports. MSDS of nutrientsmay be available that will tell the whole story)
^ The Ca:Mg on this one is an absolute fucking prank (ofc, tap doesn't help), maybe it's suited for dwc but I almost cannot imagine it
This is something like canna coco nutrients:
However, if your feed is low in Mg that is no disaster. You can use magnesium nitrate in veg and switch to sulfate in flower using the ppms from Grapefruitroop. That is beautiful. very yin-yang
Same thing for potassium which you can get as K nitrate or K sulfate.
Here are some random hydro A&Bs anyone can buy today
(Always substract 63 Ca, it is my tap water. ppms based obviously on what the manufacturer reports. MSDS of nutrientsmay be available that will tell the whole story)
^ The Ca:Mg on this one is an absolute fucking prank (ofc, tap doesn't help), maybe it's suited for dwc but I almost cannot imagine it
This is something like canna coco nutrients:
However, if your feed is low in Mg that is no disaster. You can use magnesium nitrate in veg and switch to sulfate in flower using the ppms from Grapefruitroop. That is beautiful. very yin-yang
Same thing for potassium which you can get as K nitrate or K sulfate.
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Thx 4 the tip.
WHat I till don't get however if we forget about watts and talk about par.
Why do plants under white leds's cause these issues at the same par value ? I mean 350 ppfd if 350 ppfd right? No matter if the source is the sun, a blurple, HPS or white led, 350 ppfd is 350 ppfd right? Why can my plants handle a higher ppfd value under blurples without freaking?
I hear people say increased photosynthesis and feed demand bc of intense light. But that would mean that ppfd or par is not the same for blurple and white led???. So 300 par blurple is easier to handle than 300 par white led light? Why??? The light intensity or output should be the same no, regadless of the light source??
Why must I give my plants all these extra additives at the same par value under different colors?
I can understand that they are more efficient and that 50w white led is 100 w blurple; but forget about watts, we talking par now.
Can you, or someone here give me the logical explanation? I hate it when I don't understand something so please enlighten me.
And yeah I am an organic grower, so I have big problems with growing that way. For me adding calmag is already extreme lol. I normally just prepare soil mix and then water with great results and already for +20 years.
I want to find a way or adapt the soil amending so I can grow with straight water. If this is not possible under these LEDS(the white ones) then I am not sure if they are for me..
SuperBadGrower
Active member
Like I said (IIRC), I think it might have to do with the % of blue light. But I am just speculating.
Blue photons are the most energetic because they have the shortest wavelength.
White LEDs as you probably know are phosphor converted, they are blue leds with a layer. They look white but they all have a significant amount of blue light. 4000/5000K pc leds and up all will have high B:R ratio.
The B:R ratio in purple lights can vary.
But it seems to me the % blue is lower there. (HPS has even lower %blue)
You can't really tell the true B:R by the spectrum - just because the blue peak is higher doesnt mean there is more blue than red. But it is an indication.
The problem is always at the top. Leaves turn pale and the nutrients are transported from the rest of the plant. (if possible)
Nearly ALL the blue light is absorbed by the very first leaf it hits.
No HID light in the world has as much "punishing" blues as LEDs. MH might be a close contender but its spectrum distribution is gentler. Additionally there is plenty of info about damage to humans from LEDs. Circadian rhythm, eye damage. Humans are also disturbed by disproportionate amounts of blue photons.
It's also worth looking what the PC leds lack. Look at 480nm, almost nothing there. Theres always a cyan dip. The greens are not that strong either compared to HPS. Far red is insignificant level <90CRI. Green & far red penetrate, and cause more photosynthesis in lower leaves.
If more % of the light is green and far red, that simply means photosynthesis is distributed vertically. More parts of the plant can process smaller loads of work, instead of just the top leaves having to work a BIG load.
So when your feed is not on point, those top leaves, which absorb almost all the light cannot handle the big work load.
^ I have no idea if any of that holds water really. it's mostly bro-science from my own anecdotal observations.
Look in the work of Bruce Bugbee, I mean his white papers not the youtube videos. It's about the weight assigned to photons. There is a difference between PPF and YPF (yield photon flux), the latter weighs photons. Not entirely sure
I seem to recall something about quantum sensors weighing all photons 400-700nm equally. If you look for Bruce's explanations of YPF you will find the information.
I'm not saying any of this is right, this is just my speculation, thoughts and opinion. There are also so many variables (in LEDs) that it will be hard to say what's what (to add to that, there are even different phosphor blends to achieve different qualities of results, for the same CCT). In the future I think we will have green/far red supplementation. everyone will forget 660 nm which is already plentiful. (It's just added to increase µmol/J)
No ideas here, indoor wise. I've seen packs of dolomite lime that has 19% Mg in it. I would just add that + complete tomato/fruit NPK, and top dress the NPK once if needed.
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Thank you for your usefull reply, I get the feeling your username isnt quite correct 
Yeah I already added extra dolomite lime on top but it take a while to get started, up to now no reaction.
But yeah thanks again will read that later tonight as I really feel a need to understand all of this better and I don't want to start giving liquid nutrients.
Yeah I already added extra dolomite lime on top but it take a while to get started, up to now no reaction.
But yeah thanks again will read that later tonight as I really feel a need to understand all of this better and I don't want to start giving liquid nutrients.
SuperBadGrower
Active member
No problem dude, scholar.google.com & also look in the citations. Goldmines. If you cant access an article try sci-hub. But dont act rashly. once you start reading you will find many things. By the time you stop reading you'll have forgotten what you read in the beginning hahah
He himself grows with a standard agriculture fertilizer, I think it's a one part (one tank) but I'm not sure. Ag fert sellers like yara make them, it's without calcium. Because everybody and their mother already has calcium out the wazoo (lime in medium, lime in water)
He himself grows with a standard agriculture fertilizer, I think it's a one part (one tank) but I'm not sure. Ag fert sellers like yara make them, it's without calcium. Because everybody and their mother already has calcium out the wazoo (lime in medium, lime in water)
WHat search terms did you exactly use in scholar google? I already looked a while back but did not find what I was looking for. I did find lots on info on co2 there though.
I love scholar google for finding accurate information. Also during this corona BS it has been usefull to confirm or deny things that were being said in the media and/or conspiracy sites. There was a study from one of the teams that is developping a vaccine now and they said it will be released via a special rush procedure so there won't be any time to study side effects. I'm like yeah give me the vaccine but test it first, I'll wait a couple of years no prob. But yeah sorry going off topic....
Yeah they do however add epsom salts to their feed with the yara nutrients, at least they did at Bedrocan.
I love scholar google for finding accurate information. Also during this corona BS it has been usefull to confirm or deny things that were being said in the media and/or conspiracy sites. There was a study from one of the teams that is developping a vaccine now and they said it will be released via a special rush procedure so there won't be any time to study side effects. I'm like yeah give me the vaccine but test it first, I'll wait a couple of years no prob. But yeah sorry going off topic....
Yeah they do however add epsom salts to their feed with the yara nutrients, at least they did at Bedrocan.
Btw This is how my plant normally look and how I want them to look. I gave them all a veg tab after your reply. Normally this feeds a plant for 2 months, lets see of it helps in any way. If they die from your advice I'm gonna go Liam Neeson on your ass, I will find you!!!! (just kidding).
I am avoiding liquid stuff. Added more magnesiumlime on the top soil as well. ANd I did order one calmag 2.0 bottle (calmag with iron and other micronutrients) to see if it helps in any way. But that is as far as I would like to go with bottled stuff. Oh yeah and I spray them with epsom salts that I had lying around here till the calmag gets here.
I am used to feeding the soil and not the plant, it has always worked and I am trying to make it work now as well. I my switch if I am really forced. In the meantime the vegging plants are getting too big.
They were supposed to be flowering already but I cant flower them untill I solve the issue. This is the second grow this year that has weeks delay cuz of me not being used to white leds.
I was training them, made scrogging nets for each pot, took me hours of work. They had the perfect shape to be flowered, 8-10 uniform branches for ditto colas. But now all that work has gone down the drain as they are way too big now.
But I am a stubborn asshole, I'll get it and won't give up even if I sometimes feel like smashing those lights
@Superbadgrower: consider yourself a lucky man! (plus it saves me time as well: I won't have to start looking for you.
Your advice totally worked!! I still havent received my calmag but I have been giving them epsom salts twice a week and I topdressed a high dose 2 weeks ago. And new shoots are actually starting to look like normal healthy shiny plants.
Also a totally yellowed motherplant is becoming green and shiny again. It' crazy, I have an identical motherplant on the 250MH side and that one hasn't been topdressed for 6 weeks and still healthy vibrant green. Its bizarre how much more they eat. Plus it was difficult for me to find the solution because the symptoms didn't look like any dificiency I ever saw. Its not like they look N deficient, it' just that yellowing and chevron stripes thing; guess this is a white led only symptom of nute deficiency? ???
So yeah thx.
It seems so counterintuitive giving them so much food. Under other lamps my plants would be overfertilised. I am used to giving them just enough nutrients but always on the lower side of the spectrum.
Still need to adjust, but now I know the solution. But the timing and dosage of everything (organics take a while) will change. But at least I got them healthy
Feels good cuz I was almost foaming at the mouth after 4 months.
I wonder if this will also work under the fluence as I had totally different issues under that one. Only one way to find out I guess
SuperBadGrower
Active member
haha 
Excellent...glad I could offer something useful to you
I agree, it's pretty counter intuitive to have to feed so much. I wasnt confident with it at first. Honestl, nowadays I would rather have a little too much than just too little. The stunting from "not enough" is worse than the damage caused by "a little too much". Just my opinion
Excellent...glad I could offer something useful to you
I agree, it's pretty counter intuitive to have to feed so much. I wasnt confident with it at first. Honestl, nowadays I would rather have a little too much than just too little. The stunting from "not enough" is worse than the damage caused by "a little too much". Just my opinion
eyesdownchronic
Active member
This may have already been explained, but just to clarify.
Yes ppfd=ppfd, but ppfd is a measure of light quantity. ie How many photons are hitting your plant in x amount of time. But, there is another measure of light which is light quality. Light quality is based on the wavelength of light which is hitting your plant. Light quality has more facets to it than does light quantity. Firstly, you can base light on its absorbtion level. For instance, green light has a very low absorbtion rate, (why plants look green,) where as both red and blue are peaks of absorbtion. Also, different light wavelength have different energy levels, with blue being a higher energy lightthan red.
Where it really kind of gets confusing is when you further add in the actual plant machinery which is responsible for photosynthesis, and the pigments which absorb different wavelenegths. Trying to learn about photosynthesis quickly leads down a long ass rabbit hole of information.
