Need Information on Cal/Mag Deficiencies When Using Led Lights

[coreywebster]

35,000lum and I tried raising with no change. If anything closer for more heat would seem to support the argument.

I'm gping to try upping my mag to 80 and see what happens, 80 isn't that high even.

I get where your coming from, just not inline with what happened to me when I set up my QBs the first time.
Since LEDs don't heat surfaces like a IR light you would have to get very close to make a difference in leaf temp and would be way past light burn by that point.
My plants got destroyed in a few days when I set up my lights 12" away from canopy, they looked like every deficiency all at once.
Once I raised to 18" I never saw the problem again.

The other thing is your pics don't look at all like a magnesium deficiency. I could see why someone might think a calcium def and even a potassium def but magnesium deficiency doesn't look like that. But then I am sat here and only have a pic to go on.

I hope you get the issue sorted out regardless.

 

[shawnery]

I think it looks like late stage mag def but just different then normal I also thought cal or pot but potassium looks so much different.

Here is probably some unrelated info. My ph has been going down since stretch ended and I haven't been able to figure it out why. Roots are tits and white as day one. Water is changed regularly. So I thought it must have something to do with ion exchange from a difference in nutrient absorbtion.

The last two days I kept everything the same except I upped my mag from 50 to 80ppm. Today starting my 5th week of flower I saw my first rise in ph since the end of stretch. The only thing, nothing else has changed not one minuscule ioda of nothing, that has changed is my mag level.

Probably unrelated and coincidental but then again I don't believe in coincidence at all!

 

[cannabineer]

If anything with LEDs I think most people use too much calcium.
HID gives nice bright spots right under the bulb, but to the best of my knowledge a dialed in LED system is going to have higher levels spread more evenly through the canopy and therefore lead to higher transpiration. Calcium being passively taken up can start becoming a problem. It has a double positive bond so it really binds to shit quite easily

There are other double-positives, so an electrostatic argument doesn't really work. The plant is really good at regulating how much calcium it takes up, and I don't think calcium becomes a problem until there is enough to lock out magnesium, iron and the other two pluses. So I am leaning toward the "different temps, different metabolic patterns" hypothesis.

 

[cannabineer]

Well, I do agree with some information here but let's look at the chlorophyll A molecule.

The molecular structure of chlorophyll aconsists of a chlorin ring, whose four nitrogen atoms surround a central magnesium atom, and has several other attached side chains and a hydrocarbon tail.

If LED's truly raise photosynthetic activity to a point that the plant cannot upkeep chlorophyll synthesis we would see nitrogen stolen from the bottom leaves first as chlorophyll A has 4 times the nitrogen molecules as it does magnesium molecules.

What I do believe is that the plant actually requires less calmag as the photorespiration reduces under lights that do not raise internal leaf temperatures from "wasted" light. (LED's) and regularly adding calmag results in a lockout.
Raising ambient temperatures can work but doing research on a plants ability to efficiently use nutrients under a high transpiration rate isn't an effective use of nutrients and lies under the category of wasteful practices.

Take it easy and watch for any spreading symptoms, a lot of things in a grow room could be very short lived and resolved without excess interventions.

I don't think there is a correlation between N supply and amount of chlorophyll. The plant's biochemical suite is remarkably flexible, and its primary chlorin production engines are under sophisticated control by e.g. hormones.

So I don't think we can correlate chlorophyll production to availability of N. Even under ideal conditions the amount of N that goes to chlorophyll (and not other proteins etc.) is tiny.

 

[curious2garden]

.....snip........ I don't think calcium becomes a problem until there is enough to lock out magnesium,.......snip.......

Precisely and then you are locked out. I believe it's more likely heat but his idea is worth considering. I don't run LED so this isn't something I can speak intelligently on.

 

[ShedsAndTents]

I don't think there is a correlation between N supply and amount of chlorophyll. The plant's biochemical suite is remarkably flexible, and its primary chlorin production engines are under sophisticated control by e.g. hormones.

So I don't think we can correlate chlorophyll production to availability of N. Even under ideal conditions the amount of N that goes to chlorophyll (and not other proteins etc.) is tiny.

I must disagree:
https://www.sciencedirect.com/science/article/abs/pii/S116103011480141X
https://www.sciencedirect.com/science/article/pii/S2214317316301196
http://www.pmf.kg.ac.rs/kjs/volumes/kjs31/kjs31bojovicmarkovic69.pdf
"Chlorophyll content is approximately proportional to leaf nitrogen content, too (EVANS, 1983)"

The amount of N used to synthesize chlorophyll is greatly relative to leaf mass which we all know as "growth"
https://link.springer.com/article/10.1007/BF00377192

I'm just assuming that the real background cause is narrow banded LED's that do not produce wavelength necessary for certain metalbolic or enzymatic synesthete. Getting away without these wavelengths may be a result of soil structure and rhizospheric activity as we all know a mycorrhizae can synthesize enzymes and less known those enzymes can later be found in shoots (Without the same metabolic activity required from the plant itself)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3209872/

 

[ShedsAndTents]

Here's a few other ones good for the read.
https://www.greenwaybiotech.com/blogs/news/whats-the-function-of-nitrogen-n-in-plants
(basic with good information)

http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447042&topicorder=2&maxto=8

https://www.researchgate.net/publication/309704090_Role_of_Nitrogen_for_Plant_Growth_and_Development_A_review
(This one gives a little insight on middle eastern strains)

https://www.pthorticulture.com/en/training-center/role-of-magnesium-in-plant-culture/
"Magnesium deficiency often is caused by lack of application, but it can be induced if there are high levels of calcium, potassium or sodium in the growing medium."

"Magnesium toxicity is very rare in greenhouse and nursery crops. High levels of magnesium can compete with plant uptake of calcium or potassium and can cause their deficiencies in plant tissue."

https://chemistry.stackexchange.com/questions/49308/why-is-the-magnesiumii-ion-preferred-over-other-ions-in-chlorophyll
This little debate has wonderful information as well.

Edit:
http://gsrpdf.lib.msu.edu/ticpdf.py?file=/1970s/1972/721101.pdf
This is an easy to digest one too.

 

[cannabineer]

I must disagree:
https://www.sciencedirect.com/science/article/abs/pii/S116103011480141X
https://www.sciencedirect.com/science/article/pii/S2214317316301196
http://www.pmf.kg.ac.rs/kjs/volumes/kjs31/kjs31bojovicmarkovic69.pdf
"Chlorophyll content is approximately proportional to leaf nitrogen content, too (EVANS, 1983)"

The amount of N used to synthesize chlorophyll is greatly relative to leaf mass which we all know as "growth"
https://link.springer.com/article/10.1007/BF00377192

I'm just assuming that the real background cause is narrow banded LED's that do not produce wavelength necessary for certain metalbolic or enzymatic synesthete. Getting away without these wavelengths may be a result of soil structure and rhizospheric activity as we all know a mycorrhizae can synthesize enzymes and less known those enzymes can later be found in shoots (Without the same metabolic activity required from the plant itself)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3209872/

Thank you for this information! @Singlemalt, opinion?

 

[RedLebFarmer]

Here's a sickly and deficient plant grown under the incomplete spectrum of LED at day 42.

Looks so sick dude you should kill it and start again imho

 

[OLD MOTHER SATIVA]

Me
. had used 300 ppms for couple years up until last crop and was talked into 600+..nah..i am going back to under 400

update

.nah i am staying at 600 ppm+ now

they are growing way better..

happy new year

 

[curious2garden]

Looks so sick dude you should kill it and start again imho

That's from 4/2017 and I doubt it was his.

 

[hybridway2]

So it's been a few years since others here have admitted to suffering from LedDefficiency.
I just read most of it & i gather no solid answers but many possibilities. Or several solid answers that do not apply to everyone.
Hard to tell.
What i can say is I've tried just about everything discussed in this thread before seeing it. My main battle with LedDefficiency lasted a lil over 2 yrs. 50% of the room doing well while the other 50% shit the bed under any white leds.
Almost never have it in Veg (except the second time i tried to do a SBS vs Burple). That was a hurting veg.
But to me the main problems have always happened around wk 3 of flower. And usually starting on the top wherever the white leds photons hit the plants.
Now, in this thread there are many hypothetical ways to combat this. Raise the lights or dim, is one of the key factors to recovery & prevention, I've found. Along with Magnesium. Then there's the uncharted territories.
Fxck what your par meter says. Read the plants.

 

[OLD MOTHER SATIVA]

there are so many of us who just do not understand this "deficiency" thing that seems to plague you bro

if you give em enough calcium nitrate [and even just forget about the mag]..along with your normal npk
..they grow fine..

and epsom doesn't hurt either..

 

[hybridway2]

there are so many of us who just do not understand this "deficiency" thing that seems to plague you bro

if you give em enough calcium nitrate [and even just forget about the mag]..along with your normal npk
..they grow fine..

and epsom doesn't hurt either..

You & They don't understand? There is thread after thread about this if one searches. Its not like I'm the only one losing plants to this.
I can show you my room rn with 1/2 the room at 90-95% health & the other half at 60% , looking better then 60% now cuz i fight it the whole way through. Then there's x2 plants that just crapped out with yellowing leaves over the Trinity raised to the ceiling (tons of space between light n plants, lights at 300w).
So yeah, it gets a lil annoying when a 4x7 goes to waste & its one of my favorite daytime smokes too.
TechNaFloras NPK may not be what i need here & am currently doing a SBS in veg only using Jacks vs. GH. I know veg aint gonna tell me what i need to know but its a start.
The 2 lines are neck to neck after 3 weeks of feeding.
When someone else loses 400-700g plants do to this issue many have it becomes a problem. I'm not that shy n have NO Problem looking like the fool here by admitting i do not have it down after 2+ years. If that's what it takes to share the truth about my experiences. A Fool is exactly what i feel & look like, i know.
The good plants come out so good that it keeps me going.
I understand some species may need something different then the next but common now, this is weed. How is it some plants are telling me they are Slappy Happy while others are choking? Same conditions all around.
That's why I'm so determined to get to the bottom of this.
You have been here for awhile. You see i no longer have any nute burn or the issues i had chasing my LedDefficiency, trying to cure it with random products on the shelf. Only defficencies now & on 1/2 the plants not all. So its a step in the right direction.
Im trying bud, believe you me, im trying.

 

[Airwalker16]

You & They don't understand? There is thread after thread about this if one searches. Its not like I'm the only one losing plants to this.
I can show you my room rn with 1/2 the room at 90-95% health & the other half at 60% , looking better then 60% now cuz i fight it the whole way through. Then there's x2 plants that just crapped out with yellowing leaves over the Trinity raised to the ceiling (tons of space between light n plants, lights at 300w).
So yeah, it gets a lil annoying when a 4x7 goes to waste & its one of my favorite daytime smokes too.
TechNaFloras NPK may not be what i need here & am currently doing a SBS in veg only using Jacks vs. GH. I know veg aint gonna tell me what i need to know but its a start.
The 2 lines are neck to neck after 3 weeks of feeding.
When someone else loses 400-700g plants do to this issue many have it becomes a problem. I'm not that shy n have NO Problem looking like the fool here by admitting i do not have it down after 2+ years. If that's what it takes to share the truth about my experiences. A Fool is exactly what i feel & look like, i know.
The good plants come out so good that it keeps me going.
I understand some species may need something different then the next but common now, this is weed. How is it some plants are telling me they are Slappy Happy while others are choking? Same conditions all around.
That's why I'm so determined to get to the bottom of this.
You have been here for awhile. You see i no longer have any nute burn or the issues i had chasing my LedDefficiency, trying to cure it with random products on the shelf. Only defficencies now & on 1/2 the plants not all. So its a step in the right direction.
Im trying bud, believe you me, im trying.

That's the beauty of using RDWC with multiple strains, they take what they need from the nute solution and that's it. In soil, it's a whole different ball game.

 

[Kushash]

You & They don't understand? There is thread after thread about this if one searches. Its not like I'm the only one losing plants to this.
I can show you my room rn with 1/2 the room at 90-95% health & the other half at 60% , looking better then 60% now cuz i fight it the whole way through. Then there's x2 plants that just crapped out with yellowing leaves over the Trinity raised to the ceiling (tons of space between light n plants, lights at 300w).
So yeah, it gets a lil annoying when a 4x7 goes to waste & its one of my favorite daytime smokes too.
TechNaFloras NPK may not be what i need here & am currently doing a SBS in veg only using Jacks vs. GH. I know veg aint gonna tell me what i need to know but its a start.
The 2 lines are neck to neck after 3 weeks of feeding.
When someone else loses 400-700g plants do to this issue many have it becomes a problem. I'm not that shy n have NO Problem looking like the fool here by admitting i do not have it down after 2+ years. If that's what it takes to share the truth about my experiences. A Fool is exactly what i feel & look like, i know.
The good plants come out so good that it keeps me going.
I understand some species may need something different then the next but common now, this is weed. How is it some plants are telling me they are Slappy Happy while others are choking? Same conditions all around.
That's why I'm so determined to get to the bottom of this.
You have been here for awhile. You see i no longer have any nute burn or the issues i had chasing my LedDefficiency, trying to cure it with random products on the shelf. Only defficencies now & on 1/2 the plants not all. So its a step in the right direction.
Im trying bud, believe you me, im trying.

That's the beauty of using RDWC with multiple strains, they take what they need from the nute solution and that's it. In soil, it's a whole different ball game.

If I recall hybridway2 the problem is more pronounced in RDWC than it is in soil. Right?
Is that fly problem over hybridway2?
One species never mentioned was the soldier fly, larvae might have been in the EWC's along with the mites.

 

[wietefras]

That's the beauty of using RDWC with multiple strains, they take what they need from the nute solution and that's it.

That's not true at all though. Plants can not pick and choose what they would like to "eat".

 

[f series]

Just raise your lights

 

[wietefras]

Its not like I'm the only one losing plants to this.

How could you lose plants due to a calcium deficiency? You see the deficiency, fix the problem, done. It's one of the easiest deficiencies to spot and correct for.

And no there is no "LedDefficiency", it's just that passive uptake is a little lower due to lower transpiration rates since the plants tend to be somewhat colder under led lights (less direct heat from leds compared to HPS/sunlight). Which can also be "fixed".

 

[Airwalker16]

That's not true at all though. Plants can not pick and choose what they would like to "eat".

They absolutely can and do. When the roots are submerged 24/7, it's able to take what it needs. You can still burn them if ppms are far too high, but its not like when you water a medium to dry out and literally BURN root zones from drying salts and build up.
Rdwc keeps roots wet constantly. Always feeding.
Coco, soil, and even rockwool once dried out, can't deliver food. So it sits there until its wet again, often times further raising the ppms the roots will ACTUALLY receive, VS what you mixed at, and able to be uptaken by the root zone.