I'm stumped, what am I doing wrong??

PJ Diaz said:

Sorry bud, I'm gonna use BlueLab as a legitimate reference source before "Grow Weed Easy", each and every time.

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Did you even read your link? She contradicts what you are saying with her bullet point list. Her byline even says she's a story teller.
It's a glorified marketing blurb paid for by blue lab.

His light is dimmed to 50%.

PJ Diaz said:

His light is dimmed to 50%.

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At 12 inches.

sunasun said:

At 12 inches.

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Yep, shouldn't be an issue.

This seems like a Deja-Vu of last time you were wrong about thinking someone had issues with light intensity:

PJ Diaz said:

Yep, shouldn't be an issue.

This seems like a Deja-Vu of last time you were wrong about thinking someone had issues with light intensity:

Light burn, or more?

Rdwc system clones transplanted 8/13 Temp: 80-83 Humidity: 40-60 Res temp: 67-68 General hydro nutes with Lucas formula 580ppm last check Ph-5.8-6 Is this light burn or do I have more going on? Please let me know if I need to supply more Information. Two diff plants in photos Thanks...

www.rollitup.org

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Yep, he ended up burning his plant following your advice. Congrats you win, I'll bow out so you can continue to spread falsehoods.

Diagnosing plants from a few photos is difficult. It's fairly easy to see a plant is deficient of something, but understanding why it is is much more difficult and more important.


I wish people used EC instead of ppm, because how are we to know which ppm scale they are using. Anyway... They are feeding something like 1.1-1.5ec. if it is 1.5ec then surely it is not underfeeding? Would the plant look like that even if was just 1.1ec? I would not feed the whole canna line of nutes at full strength like some suggest, but I could be wrong.

Bro u definitely have light stress on the top. Believe it or not. Top lighter then bottom, yellowing start between the veins, tips brown and curl upwards.
Now if u also have nute lock that's another issue altogether. Bottom leaves got something going on. U are in the easiest medium to fix any issue like that.
But a 300 watt light at 50%. 150 watts for that size plant in veg is not needed. In late bloom maybe. 150 watts should be 18" at the closest and thats for bigger and healthier plants. Whenever there's an issue light should be turned down anyway to help plant recover. Blasting it with light only makes issues worse.
And no its not overfed either.

PJ Diaz said:

Did you not see all the tip burn in his plants? That's not a light issue, it's an over fertilization issue.

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There are several deficiencies that cause necrosis at the tip of the leaves, so tip burn by itself doesn't mean over-fertilization. One would be a magnesium deficiency - it starts with interveinal chlorosis on the old growth and if it's not corrected, the tips become necrotic and work inward.

One important piece of information is where did that interveinal chlorosis start - at the bottom of the plant or top of the plant. If it started at the bottom of the plant and never got better and started to spread to the top of the plant, then it's probably a really bad magnesium deficiency. However, there is old growth at the bottom of the plant that is green. If it started at the top of the plant, then it is light stress because this looks nothing like an iron or manganese deficiency (the deficiencies that exhibit chlorosis on new growth first).

Being that he's using 300W dimmed to 50% at 12" and the only thing that's changed in his setup from his previous successful grows is using this more powerful light, I'd bet he was getting interveinal chlorosis starting at the top of the plant - light stress.

If it were over-fertilized, there wouldn't be interveinal chlorosis. If it were over-fertilized, then when he lowered the EC from 1.5 to 1.0, it wouldn't have continued to get worse.

I used to run this exact light. I've had some plants almost grow into the lights and not have it do anything like this.

sunasun said:

Over nuted would be dark green, not bleached as is frequently common when given too much light. She can't keep up with the light being given , back off the lights till she's ready.
And yes you're right light stress stress can cause burnt tips. The curling leaves, bleaching and short internodal spacing also tell you it's light stressed.
Also, notice that the leaves towards the bottom are dark green the furthest away from the light. But no, it can't be light stress, for you and your merry group have proclaimed it, despite all evidence to the contrary.

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Not all nutrients will cause the dark green. Some nutrients when given in excess will first appear as a deficiency in whatever it is locking out. I've used this exact lamp in the past. Its 4 bars each with 3 rows of diodes. I have had plants grow within an inch of the light on full and don't recall any bleaching. They just aren't pushing the LEDs that hard.


This light at 50% there is zero% chance his issues are being caused by too much light. The plants not a baby. It's gotta be 7-8 weeks at least

But op isn't even answering questions and I respect all you guys opinions so I'm out

MannyPacs said:

I used to run this exact light. I've had some plants almost grow into the lights and not have it do anything like this.


Not all nutrients will cause the dark green. Some nutrients when given in excess will first appear as a deficiency in whatever it is locking out. I've used this exact lamp in the past. Its 4 bars each with 3 rows of diodes. I have had plants grow within an inch of the light on full and don't recall any bleaching. They just aren't pushing the LEDs that hard.


This light at 50% there is zero% chance his issues are being caused by too much light. The plants not a baby. It's gotta be 7-8 weeks at least

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Exactly. This is a bar type LED, which is meant to be run close to the tops. Now if this was a 300w quantum board type, then I might agree with @sunasun that the light was too close, but at 50% it's really not an issue for a plant at that stage.

PJ Diaz said:

Exactly. This is a bar type LED, which is meant to be run close to the tops. Now if this was a 300w quantum board type, then I might agree with @sunasun that the light was too close, but at 50% it's really not an issue for a plant at that stage.

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Bar or quantum, PPFD is PPFD and according to PAR maps by both Mars and independent testers of that light, homey is improperly blasting that plant for its current stage in life.

ec121 said:

Bar or quantum, PPFD is PPFD and according to PAR maps by both Mars and independent testers of that light, homey is improperly blasting that plant for its current stage in life.

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Do you have a par map for that light at 50% from 12-inches? It's odd that myself and others can run lights that close without these issues you are speaking of.

Why not test for nutrient burn. Test your EC/PPM at the same time of day( preferably right after lights on or right before lights off ). If your EC/PPM are dropping then she eating more then drinking( usually means under feeding ) If they go up then your over feeding. Take at least 3 days reading. Also take note of your PH it should go in the opposite direction your EC/PPM goes. If it goes the same direction(ec down and ph down) then I would check your roots for issues. If ph stays stable and your ec only moves a bit your close to the sweet spot.

Here's the par maps from the manufacturer for that light (which are likely over rated). They don't even have maps for 12-inches away. They have one for 10-inches away though, and dimmed down to 50% you can see that even at 10-inches you're looking at around 650 ppfd max at the center, which shouldn't be an issue for a plant that size. That's at 10-inches, at 12-inches it will be closer to 550 ppfd.

PJ Diaz said:

Do you have a par map for that light at 50% from 12-inches? It's odd that myself and others can run lights that close without these issues you are speaking of.

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First, can we agree on a PPFD number that is too bright for the plant at this stage without Co2 supplementation? No sense in getting into the weeds with numbers if you're going to say, "Well, plants in early veg can handle far more than that."

ec121 said:

First, can we agree on a PPFD number that is too bright for the plant at this stage without Co2 supplementation? No sense in getting into the weeds with numbers if you're going to say, "Well, plants in early veg can handle far more than that."

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Sure:

My money is on some kind of rootzone problem which lead to the plant not be able to keep up with the light. If the ec was 1.1 i would expect to see a pale plant, but not one looking like that. Neither should 1.5ec lead to that, imo.

If it were my plant... I would do a water change. Feed only a&b at 1.5ec and lower light intensity... Or maybe just run 18/6 if it was 24/0 until new growth looks good.


Oh! What do the roots look like?

The OP apparently doesn't want to participate in his own thread, so we're all kind of shooting in the dark over here.

At least he seems to be on the right track:

Calcium abundance, calcium will accumulate in the leaf edges and burn them

Also looks potassium deficient due to calcium levels