LED and Calmag issues.

3rd Monkey

3rd Monkey

Well-Known Member
So, there's been some correlation between using LED lights and calmag issues, particularly a lack of calcium and sometimes magnesium.

I've been doing some testing with tomato plants under an LED. I was finally able to replicate the issue.

Now, what I have found is that it's not really a Calmag issue at all, it's a potassium issue. Let me explain.

I ran 6 tomatoes under an LED until I got the issue to arise. I fed extra calmag to 2, dropped potassium to 1/2 and cut calmag in 2, and dropped potassium and calmag in 2 of them to 1/2.

The 2 with the extra calmag were fine until a full nute feeding, then back to calcium issues.

The 2 with reduced potassium and cut calmag, did better than full nutes and full calmag. Still issues.

The 2 with reduced potassium and barebones calmag seemed to alleviate the symptoms completely and are now growing healthy again.

I don't have lab equipment and I didn't document it, which I should have but had no idea what I was trying to do yet lol. However, in my testing, it appears that it's not a lack of calmag from the LED, but an excess of K.

I don't know if it deals with spectrum or par or whatever, but I would like some input from anyone who can possibly explain this, if it can be explained.
 
ChiefRunningPhist

ChiefRunningPhist

Well-Known Member
3rd Monkey said:
So, there's been some correlation between using LED lights and calmag issues, particularly a lack of calcium and sometimes magnesium.

I've been doing some testing with tomato plants under an LED. I was finally able to replicate the issue.

Now, what I have found is that it's not really a Calmag issue at all, it's a potassium issue. Let me explain.

I ran 6 tomatoes under an LED until I got the issue to arise. I fed extra calmag to 2, dropped potassium to 1/2 and cut calmag in 2, and dropped potassium and calmag in 2 of them to 1/2.

The 2 with the extra calmag were fine until a full nute feeding, then back to calcium issues.

The 2 with reduced potassium and cut calmag, did better than full nutes and full calmag. Still issues.

The 2 with reduced potassium and barebones calmag seemed to alleviate the symptoms completely and are now growing healthy again.

I don't have lab equipment and I didn't document it, which I should have but had no idea what I was trying to do yet lol. However, in my testing, it appears that it's not a lack of calmag from the LED, but an excess of K.

I don't know if it deals with spectrum or par or whatever, but I would like some input from anyone who can possibly explain this, if it can be explained.
Click to expand...
Tap water? What pH down? Nitric? What ppm of starting water? What brand fert?

I'm going to venture out and repeat my lingering hypothesis that I've had for awhile now, its possible you actually had a low K and high Ca nute solution. That's why the barebones Ca alleviated the symptoms. I'm finding MJ likes Zn, Mn, S, and K more than what I've traditionally read. I had issues too, but I'm leaning towards high mineral content in starting water which is neutralizing my nutes and messing up ratios. I think if you're using tap water, you should use less Ca, more K and Zn. GH has a nutrient line tailored for hard water but I've never tried it.
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I've also been wondering if there's something electromagnetic happening to the plant from the LEDs. 110v (high V qb example) shouldn't be sufficient to produce EM fields large enough to mess with the plant, I wouldn't think, but I'm wondering if the lights are ionizing the water around them, this phenomenon had been perplexing me as well..

Some swear its VPD, that if you just inc your RH to around 60% that the plant can't evaporate as much water into the air because the air is more saturated at the higher RH, and so the plant keeps its moisture better and doesnt burn under the intensity of the LED. If its not transpiring as much it's not drinking nutes as much, and also visa versa, when it's dry its transpiring lots and drinking lots and you can get nute burn from the constant drinking trying to replace what it evaporated.. Or so the logic goes..
 
budman111

budman111

Well-Known Member
3rd Monkey said:
  1. The 2 with the extra calmag were fine until a full nute feeding, then back to calcium issues.
2. The 2 with reduced potassium and cut calmag, did better than full nutes and full calmag. Still issues.

3. The 2 with reduced potassium and barebones calmag seemed to alleviate the symptoms completely and are now growing healthy again.

.
Click to expand...
I had the issue years ago and it is Calcium that's needed in flower, I proved it years ago and it's due to a certain red nano-meter causing the issue:

1. you had Calcium issues because you gave *extra* calmag

2. Subjective if you still had issues

3. the barebones calmag was enough to pull through
 
3rd Monkey

3rd Monkey

Well-Known Member
Everything is right where it's supposed to be, I grow in a compost/coco mix and it's my perpetual garden with multiple species, under a T5 and an HPS, now an LED.

The only factor that changed for the tomatoes that I grow every year with the same medium and water is the light.

I know K wasn't too low, no signifiers on any of those plants or any of the others I grow. I have to flush the compost/coco and reapply a top dress to feed. I used GH calmag that a friend currently uses in his grow without issue under HPS.

Tap water that is filtered to 24ppm and comes out between 6.5-6.8. Swings to 7.2 in 24hrs which is when I water them again, with 20-30 percent runoff every 3rd watering.

I really think I see that it goes to excess K from the shade of leaf and the mottling that magnesium DOESNT fix. Then a dose of calmag will improve it until I top dress again. I know there's enough calcium in my top dress, just seems like the K pushes it out or goes to excess.
 
3rd Monkey

3rd Monkey

Well-Known Member
budman111 said:
I had the issue years ago and it is Calcium that's needed in flower, I proved it years ago and it's due to a certain red nano-meter causing the issue:

1. you had Calcium issues because you gave *extra* calmag

2. Subjective if you still had issues

3. the barebones calmag was enough to pull through
Click to expand...
They aren't flowering, only a foot tall.

I didn't give any calmag until the issue arose. Then it cleared up until next top dress where it seemed excess K.

The issues were inconsistent between plants based upon diet of K and Ca.

Enough with a decreased amount of K. Full strength K feeding was too much.
 
budman111

budman111

Well-Known Member
3rd Monkey said:
They aren't flowering, only a foot tall.

I didn't give any calmag until the issue arose. Then it cleared up until next top dress where it seemed excess K.

The issues were inconsistent between plants based upon diet of K and Ca.

Enough with a decreased amount of K. Full strength K feeding was too much.
Click to expand...
It's only during flower that you will need calcium with led.
 
rkymtnman

rkymtnman

Well-Known Member
i'm about done with my first grow under QBs and my first Ca issues in a while.

my first thought is what is different about QBs vs cmh or hps or mh?

lack of infra-red. so people say run your garden warmer under leds to make up the difference.

maybe that is affecting the capillary action in the leaves which brings in less K. or maybe it brings in more K? and if you have too much Ca and a lessening of K, maybe that is part of the problem? or vice versa?
 
3rd Monkey

3rd Monkey

Well-Known Member
rkymtnman said:
i'm about done with my first grow under QBs and my first Ca issues in a while.

my first thought is what is different about QBs vs cmh or hps or mh?

lack of infra-red. so people say run your garden warmer under leds to make up the difference.

maybe that is affecting the capillary action in the leaves which brings in less K. or maybe it brings in more K? and if you have too much Ca and a lessening of K, maybe that is part of the problem? or vice versa?
Click to expand...
When I lower K and run barebones Ca, it goes fine. But if I run full strength both or one of the others in higher strength, it shows issues.

I scrapped the worst 1 of each, but I will take a pic of the 3 that are left tonight when I get back in the tent.

I'll try to show what I mean.
 
rkymtnman

rkymtnman

Well-Known Member
3rd Monkey said:
When I lower K and run barebones Ca, it goes fine. But if I run full strength both or one of the others in higher strength, it shows issues.

I scrapped the worst 1 of each, but I will take a pic of the 3 that are left tonight when I get back in the tent.

I'll try to show what I mean.
Click to expand...
how about running some of your nute mixes thru a nute calculator por favor? i'd love to see what ppms you are talking about when you say low K or low Ca. how that correlates to a ppm value.

then i can put my maxibloom and cal/mg into a calculator and see what i'm running.
 
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