Deficiency in...?

Is this iron?



1000 PAR, 1500 PPM, 5.65 pH DWC

Not iron , looks more like Mg. With Iron it starts at the new tips and is very light yellow, sometimes almost white. What I see is interveinal chlorosis (yellowing between the veins of the leaf). It can have a few causes, but normally it's Mg. I see that the lower leaves look much better, so too much or too close of light is also a possibility.

That sounds like a lot of food and a lot of light. Not sure what ideal PAR and PPM numbers are, but most of the ones I see on here are only 3 digits. I'd say it's more likely too much of something than not enough...

Phytoplankton said:

looks more like Mg

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Mg can move and the symptoms are only on the new growth, so this is why I was thinking Fe.

Phytoplankton said:

I see that the lower leaves look much better, so too much or too close of light is also a possibility.

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This is probably it, though the rest of the group is loving it! I'll try spraying some Mg at the poor guy and see if that helps green up before the chop (it's a male anyhow).

weedstoner420 said:

That sounds like a lot of food and a lot of light. Not sure what ideal PAR and PPM numbers are, but most of the ones I see on here are only 3 digits. I'd say it's more likely too much of something than not enough...

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I just feel like this chlorosis is much too regular with no permanent damage to be light burn (systemic vs localized).

And the PPM is huge, but does not rise nor fall as the plants drink 4 of 5 gallons. I would expect this PPM to rise should it be too much for the environment (light, humidity, temp, co2, o2...). This, and the siblings doing great, really convince me that there is just a little something missing for this particular plant.

EDIT: Actually, the other buckets are maintaining their initial PPM. But this one, showing the chlorosis, is down about 20% (and has only drunk 2.5/5 gal).

EDIT2: PAR has been ramping up during veg, this plant has always looked like this... 500 or 1000.

Initial PPM ~1500

• N 210
• P 123
• K 305
  
  
• Ca 283
• Mg 125
• S 316
  
  
• Fe 4.7
• Cu 0.3
• Bo 01.1
• Mn 1.7
• Zn 0.7
• Mo 0.1

That's lockout. Way too much fertilizer.

Lou66 said:

That's lockout. Way too much fertilizer.

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Respectfully I disagree, can you provide a reason?

How that could be the case without a rise in nutrient strength over time?

And surely it's an antagonism, the ratio is off. But too much, no.

If you're letting them drink the solution down to the last gallon, that's not really good, and asking for problems. From too much fluctuation, to the roots possibly drying out over and over. Especially with triple the amount of nutrients needed for DWC. 500-800 is more like it. You wanna keep the solution topped up, just under the net pots. Keep it topped up the best you can, or switch to RDWC with a bigger res.

IMO we should all aim to dial the nutes in and drink to the last gallon. Anything else is waste. The humidity inside the res is 100%... the roots won't dry (but they are more massive than I would like, covering nearly 2 gal of volume and almost bound at the bottom of the 5 gal, due to this lack of water space in the upper region).

If I reduced the PPM that much, I'd also have to reduce the light. And the growth rate. Might as well use dirt.

Still looking for the answer to my first question... if anyone else besides the Mg guy wants to try actually answering it
I'm still thinking Fe and have dosed ~150 ppm between N and minors, micros with a focus on Fe, Zn, Mn. Sprayed Mg. Plant is greening.

Yup, new growth is looking good now. And RDWC looks great but we can see here how one of the generation is showing the deficiency that all are likely experiencing. Might not have seen this in one res. I prefer being able to differentiate the solution.

Nutrient Excess

Just as nutrient deficiencies can harm cannabis plants, excessive nutrient levels can also pose significant problems. Over-fertilization or imbalances in nutrient ratios can cause various leaf issues:

Nitrogen Excess

Excessive nitrogen levels can cause dark green leaves, often with claw-like leaf tips. The affected leaves may appear shiny and have a leathery texture. Overabundance of nitrogen can delay flowering and result in excessive vegetative growth.

Phosphorus Excess

Phosphorus excess is less common but can occur due to improper nutrient management. It can cause dark green leaves and may lead to nutrient lockout, affecting the plant's ability to absorb other essential elements.

Potassium Excess

Potassium excess can result in burnt leaf edges and necrotic patches. The affected leaves may curl downward and show signs of scorching. Excessive potassium levels can disrupt the balance of other nutrients.

Calcium Excess

Excessive calcium levels are rare but can happen when growers use high-calcium fertilizers. It can cause leaf tips to become twisted or curl upward. Calcium excess can also hinder the plant's uptake of other vital minerals.

Magnesium Excess

Excessive magnesium levels can lead to interveinal chlorosis, similar to magnesium deficiency. The affected leaves may become brittle and exhibit a characteristic yellowing pattern.

Excess Mg? Excess P and antagonism? I've considered lowering the P but it seems low enough already at 100 and I don't understand how this could be the issue given many flower blends run such a huge P ratio.

PSA: Chelate your ions and grow faster.

If the roots are filling the bottom 2 gallon area, then they probably swallowed up the air stones right?. Well, If the bubbles aren't popping from the surface of the solution or are blocked from doing so, then they probably aren't misting the rest of the root zone when it gets down that low. 100% humidity means nothing to help keep the bare roots cool when they are more exposed like that. Its plain water in the air, without any nutes or agents you might be using like bleach to keep the roots sanitized. Its not like you can easily hookup a chiller to all the buckets either, so your roots are dangling in the same temp as the ambient air, when they should be submerged so they stay cool.

Drop That Sound said:

If the roots are filling the bottom 2 gallon area, then they probably swallowed up the air stones right?. Well, If the bubbles aren't popping from the surface of the solution or are blocked from doing so, then they probably aren't misting the rest of the root zone when it gets down that low. 100% humidity means nothing to help keep the bare roots cool when they are more exposed like that. Its plain water in the air, without any nutes or agents you might be using like bleach to keep the roots sanitized. Its not like you can easily hookup a chiller to all the buckets either, so your roots are dangling in the same temp as the ambient air, when they should be submerged so they stay cool.

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Yes. An ode to aeroponics... my res is clean enough, why not?! Could also try more bubbles... I'm running on the very low side.

stayrange said:

Respectfully I disagree, can you provide a reason?

How that could be the case without a rise in nutrient strength over time?

And surely it's an antagonism, the ratio is off. But too much, no.

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If you have it all figured out. What is the point of the thread?

I have never seen a healthy plant with that high nutrient strength, especially in dwc that has the lowest concentration required. You probably have antagonism, because of salt stress. Reduce everything and then wait a few days. Then you can start to diagnose out what is actually going on. Raise the pH a bit too. 5,8-6,2 is usually recommended.
Diagnosing it in the current state is pointless. You have deficiencies in the leafs but the cause is not lack in the root zone but transport related.

Using the complete reservoir does not work in practice. Some elements such as nitrogen and phosphorous are absorbed by active transport mechanisms that arr more efficient than the passive uptake of eg calcium that is mostly controlled by transpiration. That results in accumulation of calcium in the reservoir and salt stress.

IME, supplementing c02 never really increased the amount of nutrients they were up taking from the solution in DWC, when dialed in. It just increased the overall rate at which it would suck down both the water and nutes at the same time. Meaning you have to top up more often, but still be using the same EC level as you would without the additional c02.. They would eat & drink faster, not necessarily want higher nute concetrations..

Lou66 said:

. That results in accumulation of calcium in the reservoir and salt stress.

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Yep.

stayrange said:

Initial PPM ~1500

• N 210
• P 123
• K 305
  
  
• Ca 283
• Mg 125
• S 316
  
  
• Fe 4.7
• Cu 0.3
• Bo 01.1
• Mn 1.7
• Zn 0.7
• Mo 0.1

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Did you add each one of them and 125 per what?
What nute are you using?

PPM is Parts Per Million

To the bucket that was low... added GH Florapro Calcium + Micros, Western States Vitamin B1 with Minors

In this bucket right now is a blend of:





https://www.amazon.com/Langbeinite-0-0-22-Sul-Po-Mag-Fertilizer-Strawberries/dp/B0BZQBKSCN