Led lights causing plants show nutrient deficiency?

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Atlsfinest

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Been trying to dial these think grow model W led lights for about a year now and I just can’t seem to figure out what’s going on after months and months of trial and error I finally thought I figured it out but still having the same issues these lights seem to be messing with my clones / plants. Light as hung more than 36 inches above plants. I’ve also have them running at 3% and I still seem to have the same issues I’ve been having for over a year now. Now this issue only gets worse if I don’t fix it I’ve gotten to the point where I’ll just end up tossing them cause they get really ugly and leaf’s get crispy and yellow. Environment is dialed in VPD etc. I’ve had this issue happen in promix and I’m now in ffof. What is strange to me is that my mothers are under purple led China lights and they’re doing amazing not any signs of anything they’re 6 months old and it’s always and issue when I bring into my flower room with the think grow model W lights white light leds. I’ve read that leds will cause calmag deficiency since the plants are working harder. If anyone has had this issue please get at me please I’m really tired of seeing my plants in this state and thinking of tossing the towel in but I’m not a quitter really want to make this room worth while.
 
Led lights causing plants show nutrient deficiency
Led lights causing plants show nutrient deficiency 2
Led lights causing plants show nutrient deficiency 3
Led lights causing plants show nutrient deficiency 4
Led lights causing plants show nutrient deficiency 5
BigBlonde

BigBlonde

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That does look like it could be light burn on some of those leaves. My first thought is to wonder if the dimmer on your light is working properly. Have you taken any light level readings with a meter or phone app?
 
Imzzaudae

Imzzaudae

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The brown blotches look like Calcium deficiency.
The yellowing leaf edges and light green color look like Magnesium deficiency.
The canoeing looks like light stress.
Purple Is likely potassium deficiency.
These clones are way under potted and over watered.
Leaf tips curling down, Clawing burned tips. Excessive nitrogen.
Take a look at water and fertilizer solution PH these plants look locked out.
At this stage you should have them in 3 to 5 gallon pots, in a simple potting mix feeding something to help stimulate root growth like 5-15-5 or something like this rather than a high nitrogen fertilizer.

Download the Light meter app for your smart phone. 8000 to 10,000 lux is more than enough light for clones or early veg.
Measure at the canopy. 10,000 max.

I'm thinking that this is a PH lockout issue as much as a little hot on nitrogen and lighting.
 
A

Atlsfinest

22
3
That does look like it could be light burn on some of those leaves. My first thought is to wonder if the dimmer on your light is working properly. Have you taken any light level readings with a meter or phone app?
I haven’t taken any measurements but the dimmer works I’m sure I can see it dim as I change settings. I set it to 1% and I’m going to foliar spray with Epsom salts for the mag def that’s what a lot of ppl have been claiming they are facing the same issues with led lights.
You got it champ. Turn your light down. Old growth won't heal. Look at the new growth to see if you're making progress.
You could be right about the pH lockout but I'm inclined to think "over-watered" and too much light and that the nutrients are actually in the soil. Fixing the watering practice and turning down the light should get things moving forward.
I don’t think it’s over watered I’ve has this issue on larger plants that I’ve vegged under the purple chine lights to test my theory out on the lights and when I would place them in the flower room a week later they would show the same signs and they were in larger pots as well so I’ve ruled that out it had to be the lights
 
BigBlonde

BigBlonde

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I haven’t taken any measurements but the dimmer works I’m sure I can see it dim as I change settings.
That's good. I thought it was unlikely, but worth considering. Sometimes the unexpected happens. Reducing the lights can lower a plant's stress.

I set it to 1% and I’m going to foliar spray with Epsom salts for the mag def that’s what a lot of ppl have been claiming they are facing the same issues with led lights.
Well... If the lights are ruled out, there's not much else to do than to check the soil for problems. Have you transplanted them to larger pots yet?
 
Week4Bytch

Week4Bytch

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Been trying to dial these think grow model W led lights for about a year now and I just can’t seem to figure out what’s going on after months and months of trial and error I finally thought I figured it out but still having the same issues these lights seem to be messing with my clones / plants. Light as hung more than 36 inches above plants. I’ve also have them running at 3% and I still seem to have the same issues I’ve been having for over a year now. Now this issue only gets worse if I don’t fix it I’ve gotten to the point where I’ll just end up tossing them cause they get really ugly and leaf’s get crispy and yellow. Environment is dialed in VPD etc. I’ve had this issue happen in promix and I’m now in ffof. What is strange to me is that my mothers are under purple led China lights and they’re doing amazing not any signs of anything they’re 6 months old and it’s always and issue when I bring into my flower room with the think grow model W lights white light leds. I’ve read that leds will cause calmag deficiency since the plants are working harder. If anyone has had this issue please get at me please I’m really tired of seeing my plants in this state and thinking of tossing the towel in but I’m not a quitter really want to make this room worth while.
get that vpd to 1.2 and I'm with the above with the calcium deficiency.
 
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Paleosoul

Paleosoul

67
33
Been trying to dial these think grow model W led lights for about a year now and I just can’t seem to figure out what’s going on after months and months of trial and error I finally thought I figured it out but still having the same issues these lights seem to be messing with my clones / plants. Light as hung more than 36 inches above plants. I’ve also have them running at 3% and I still seem to have the same issues I’ve been having for over a year now. Now this issue only gets worse if I don’t fix it I’ve gotten to the point where I’ll just end up tossing them cause they get really ugly and leaf’s get crispy and yellow. Environment is dialed in VPD etc. I’ve had this issue happen in promix and I’m now in ffof. What is strange to me is that my mothers are under purple led China lights and they’re doing amazing not any signs of anything they’re 6 months old and it’s always and issue when I bring into my flower room with the think grow model W lights white light leds. I’ve read that leds will cause calmag deficiency since the plants are working harder. If anyone has had this issue please get at me please I’m really tired of seeing my plants in this state and thinking of tossing the towel in but I’m not a quitter really want to make this room worth while.
Yes, LEDs require more nutrition. FFOF doesn't have enough for more than about a week or two.

With less light, you had all the nutrition your plants could handle. With additional quality light, nutrients became the limiting factors in your grow. This is a phenomenon described by Liebig's Law of the Minimum. Look it up for more information, but this classic barrel diagram explains it:

Liebigs Law of Minimum 600x600 1

Light burn will partially mimic deficiency symptoms, but they're often on the wrong part of the plants. (e.g., magnesium and potassium deficiencies show up on lower plant parts, but LED burn can mimic them on upper plant parts.) It seems that magnesium and potassium are the two nutrients that need to be increased most, with LEDs.
 
A

Atlsfinest

22
3
That's good. I thought it was unlikely, but worth considering. Sometimes the unexpected happens. Reducing the lights can lower a plant's stress.


Well... If the lights are ruled out, there's not much else to do than to check the soil for problems. Have you transplanted them to larger pots yet?
Soil is new fresh bags from the hydro store and no they’re only a week old as of now in solo cups… was going to give them another week then transplant
 
Week4Bytch

Week4Bytch

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Isn’t that little too high for freshly rooted clones ? I’m just saying that since I go based off the trolmaster vpd charthard

Isn’t that little too high for freshly rooted clones ? I’m just saying that since I go based off the trolmaster vpd chart
ahhh... freshly rooted clones..that's a horse of a different color. Proceed as usual, happy growing
 
gmolorin

gmolorin

13
13
Been trying to dial these think grow model W led lights for about a year now and I just can’t seem to figure out what’s going on after months and months of trial and error I finally thought I figured it out but still having the same issues these lights seem to be messing with my clones / plants. Light as hung more than 36 inches above plants. I’ve also have them running at 3% and I still seem to have the same issues I’ve been having for over a year now. Now this issue only gets worse if I don’t fix it I’ve gotten to the point where I’ll just end up tossing them cause they get really ugly and leaf’s get crispy and yellow. Environment is dialed in VPD etc. I’ve had this issue happen in promix and I’m now in ffof. What is strange to me is that my mothers are under purple led China lights and they’re doing amazing not any signs of anything they’re 6 months old and it’s always and issue when I bring into my flower room with the think grow model W lights white light leds. I’ve read that leds will cause calmag deficiency since the plants are working harder. If anyone has had this issue please get at me please I’m really tired of seeing my plants in this state and thinking of tossing the towel in but I’m not a quitter really want to make this room worth while.
If you suspect the intensity of the light is the problem, you can dial it in fairly easily using a great app on your phone called Photone and your dimmer. It adjusts for many, many different types of lights. It will give you PAR or DLI readings for every light type. Adjust the intensity to the growth stage you are in. There are PAR/DLI specs for all stages from seedlings/cuts, to veg, to pre-flower, to flowering/ripening. Full disclosure: I am not affiliated with the Photone app or its creators. I just use it and love it.
 
Scrogger2190

Scrogger2190

185
43
Yeah in veg I usually shoot for .85-1.0 ij flower .9-1.0 and late flower is the only time I will go above 1.0 to generally 1.2. I only keep that up long enough for it to start "defending" itself from the harsh dry environment by secreting more resin. I've also noticed that the newer leds with the dar red in them have made me need to increase magnesium/potassium the most. In some cases iron comes up.
 
A

Atlsfinest

22
3
Yeah in veg I usually shoot for .85-1.0 ij flower .9-1.0 and late flower is the only time I will go above 1.0 to generally 1.2. I only keep that up long enough for it to start "defending" itself from the harsh dry environment by secreting more resin. I've also noticed that the newer leds with the dar red in them have made me need to increase magnesium/potassium the most. In some cases iron comes up.
When you say increase mag / pot if it calls for 5ml / gallon of my base nutrient should I double or x3 that amount per gallon?
 
Scrogger2190

Scrogger2190

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I'm not getting into dosages as I'm not good at it. If there's a deficiency at current dosage then up the dosage. If plant dries out too fast increase frequency. If coco fert every time, if soil fert every 2 to 3 times. Start at 1/2 what bottle recommends. Good luck. Also this could very possibly be leaf septoria. Which is a systemic disease. I've only ran into it once and I was using promix at the time. Switched to roots organic and never had the problem again, so can't give much advice on it. Hopefully someone a little more knowledgeable can chime in.
 
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A

Atlsfinest

22
3
I'm not getting into dosages as I'm not good at it. If there's a deficiency at current dosage then up the dosage. If plant dries out too fast increase frequency. If coco fert every time, if soil fert every 2 to 3 times. Start at 1/2 what bottle recommends. Good luck. Also this could very possibly be leaf septoria. Which is a systemic disease. I've only ran into it once and I was using promix at the time. Switched to roots organic and never had the problem again, so can't give much advice on it. Hopefully someone a little more knowledgeable can chime in.
gotcha I’m feeding at .9 ec i should probably up the ec then if we’re not gonna mention dosages
 
Scrogger2190

Scrogger2190

185
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gotcha I’m feeding at .9 ec i should probably up the ec then if we’re not gonna mention dosages
From what I understand it's actually better to measure in e.c. because it's sort of like "available ppm" in the fact that the ions have the correct charge to be bound with etc.
 
Week4Bytch

Week4Bytch

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If you want to save these guys put them in fresh soil (aka repot them) into new cups or pots, whatever you got, just get them into fresh media, probably drowning them to death. And if it's Septoria...yikes, say bye bye.. tough one to battle, been there done that too.
 
citrus7144

citrus7144

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I had same issue with my plants when I first started growing under LEDs I was used to HPS and MH lights and so tried everything I could think off. I finally just used sledge hammer from Fox farms to get rid of any built up salts from to many nutes. I then only gave them water at 6 to 6.1 ph and calmag every time I watered for about 10 days. I would let the soil go dry then water. They all turned around and where fine. I now limit how much I feed my plants about 3/4 of recommended amounts a bit more often and use calmag in every water. Problem is gone through last 3 grows. Good luck and I have always found that when I have problems with any plants if I stop,flush, don't feed and watch the plants will tell me what they need. Have a great day!
 

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