Are these Zn or S def symptoms?

[elcoloan]

This Auto WwxBb is 45 days old, slowly begining her flowering phase. Growing in coco in a 2.2 gal autopot, under 60Watts of QB style LED lamp. Tent temps are 21-25C / 70-77 F, 50-66% RH.

Her last reservoir refill was 3 days ago with 540 ppm / 1.08 EC (340 ppm Megacrop v1, 85 ppm tap water, 50 ppm CalMag Pro, 65 Epsom), at 5.8 pH. Today the reservoir is at 544 ppm and ph 6.2 .

Feeling I have a deficiency of Mg and of some immobile element (Zn or S), and assuming it's not due to pH or antagonism, I mixed up a new reservoir today with a bit more nutes: 594 ppm / 1.18 EC (363 ppm Megacrop v1, 85 ppm tap water, 56 ppm CalMag Pro, 90 Epsom), pH 5.8. Hope it helps.

Any input or ideas anyone? Would really appreciate it.

I'm almost possitive she has Mg def, but not sure what the symptoms up top are.. Myabe Zn or S? They began as yellow tips that looked like light stress or nute burn on the main cola, so I first reduced EC of base nute and pulled plant away from light. But symptoms spread to other tops, so I increased EC a little bit and it seemed to get better but today i found lots of lighter areas between veins of the top leaves/tops and increased Mg def symptoms in the bottom.

Here are some pics from today:

 

[Waira]

Hey bud!

Early symptoms here, looks like it might be Zn defc., probably a plain lack-of, not a pH issue.... that said, MC has more Ca and Mg than ever, and either of these is excess (but not necessarily at toxic levels) can have antagonistic uptake issues with other nutes, some micro's like Zn included,...
It's not Mg defc.; Mg is mobile within the plant, so it will show in lower leaves first; Zn is not, so it shows on tops first and worst...

Let's try this: lose the Ca-Mg altogether, I think the MC will have plenty to maintain the coco's CEC with Ca/Mg; up the MC in kind,... Micronute defc.'s are fairly common, and without the right products to fix it, they can be a bitch to deal with... If you're in the USA, look into Earth Juice Microblast, a dedicated micro's supp' that's largely sulfate based, so that gets covered too! Filiar with that, or some other micronute supp, are the fastest way into the plant as well, usually done at half strength, using a wetting agent (critical for good results), and be sure to get the undersides of the leaves as well, there are more stomata there vs. topside... do it during lights-on when they are open for bizz, it's the only was into the leaf unless you have Optic Foliar Transport... this is a carrier solution that can temporarily penetrate the leaf cuticle and drag nutes along with it...
It's been a pain to find EU products comparable to this, so some digging around may be needed if you're overseas to USA,... an Aussie co' called Bloom Advanced Floriculture has a great line-up,... whatever you get be sure it's something with chelation, not raw minerals like basalt etc.,... too slow, weak, unstable...

 

[Simplicio]

The fact that the funny looking leaves are on top is evidence of light burn.
There should be no deficiencies when correctly using any good fertilizer, especially MC.

My guess is that they need more food for the present light distance, and lack of chlorophyll is allowing light burn.
I've had similar things happen, and giving more food, while temporarily moving lights away seemed to work.

We'd all be better off if those deficiency charts disappeared, because they distract us from what's really happening.
Not to mention that leaf appearance cannot be used to identify deficiencies, according to

Can Leaves be Used to Identify Nutrient Deficiencies? - Garden Myths

Nutrient deficiencies in the soil do affect plants. Can the physical characteristics of the leaves help identify nutrient deficiencies in the soil?

www.gardenmyths.com

 

[elcoloan]

Thanks for the input! The symptoms of the tops started spreading into lower leaves... some that were even shaded, and I got the light pretty far away and it didn't really improve. Only thing that has shown to help is increase nutes. My MC dosage was definitely too low and I was increasing supplements instead of increasing the base... dumb me. I've increased MC now and it's looking better now. BTW, I use the first version of MC, that's why I'm also using Ca-Mg and Espom salts. Plan to add Bud Explosion once the symptoms stop spreading completely and I see a better green. Could not enough P or K be causing this too?

 

[Waira]

The fact that the funny looking leaves are on top is evidence of light burn.
There should be no deficiencies when correctly using any good fertilizer, especially MC.

do you see any of the typical physical signs of light "burn", rolled edges/cupping, and dull surface often associated with it? I don't, and the tips are a tell on that here.... Do some homework again on what an immobile nutrient defc. is and how/why it shows like it does,... Meantime, let's get actual information first about his light distances before concluding in ignorance that this is a light intensity issue...

There should be no deficiencies when correctly using any good fertilizer, especially MC.

My guess is that they need more food for the present light distance, and lack of chlorophyll is allowing light burn.
I've had similar things happen, and giving more food, while temporarily moving lights away seemed to work.

You realize you contradicted yourself here? And from what I see in other MC users, 340ppm is mild dosing...
After all this time, you still don't understand that one can use nute "correctly" and still get defc. symptoms, which can be caused by a number of other things? -- pH, toxicity/antagonistic uptake issues, to say nothing of the environmental factors in play, et al... I'm hoping you do, and just phrased things poorly...

We'd all be better off if those deficiency charts disappeared, because they distract us from what's really happening.
Not to mention that leaf appearance cannot be used to identify deficiencies, according to

Maybe you would, but after 5+ years of helping people in here, I know better! You think all we do in here is pointless and futile? Do you see any complaints about "bad advise", "you fucked up my plants"? ...We have helped 1000's of people Simplicio, and have had tons of positive feedback, so there's your empirical evidence for you about that! ....Such pictures/diagrams, they are no panacea by themselves, true, but can be valuable tools in diagnosis, along with all the other info we ask for in the patient form. This is the puzzle each issue is, and we do what we can with the info we get to try and help in an actual, practical way... Cause and effect are difficult to separate doing this, and it's why nobody here is absolutist about what they say because the only way to be sure is to take leaf tissue samples (not fucking soil; tissue testing is what commercial growers I know have done at their facilities; home growers? forget it!)... Who the hell is going to send off (in-pot) soil samples for nutrient testing?? That's fine in the ground for some crops maybe, but in mediums that are dosed frequently, this will skew results, plus in smaller volumes, the dynamic of change in nutrient amounts is in constant flux between what the plant/roots are doing, and the soil microbes... What's more, nobody wants a plant physiology lesson on all the tangles and nuances nutrient uptake and interactions, it's overload, overkill and not of practical use at the time usually.... If they want to learn more, that's on the grower... Do you know what Mulder's Chart of nutrient interactions is? It sure as shit isn't for beginner growers,... Neither is diagnosis, so that's where we come in and help as best we can... Everybody knows this is very difficult work, we can be wrong for sure, but we offer the best advise we can with an eye toward not making matters worse, be conservative and careful... If we don't know, we say so and call in help if we can....
You want to buy into that hypertechnical generalization by that author, be my guest,.. I'm not saying he's wrong, but he carries it too far and clearly it's angled toward getting you to buy the books they are pimping at that site... Keep in mind that there are cannabis specific things associated with how symptoms manifest that are not necessarily applicable to all plants, and visa versa... Take that example he used about Fe defc., not affecting vein color,... often true, but not always from the many examples I've seen; do you know what a common symptom feature of Fe defc. in cannabis is, the pattern of yellowing? .... Co-defc.'s muddy the waters as well, right?

In any case, if this is your attempt to "help", do me a favor and don't! I have enough hard work in here without you coming in and pissing the punch bowl, Simplicio,...

 

[Waira]

Thanks for the input! The symptoms of the tops started spreading into lower leaves... some that were even shaded, and I got the light pretty far away and it didn't really improve. Only thing that has shown to help is increase nutes. My MC dosage was definitely too low and I was increasing supplements instead of increasing the base... dumb me. I've increased MC now and it's looking better now. BTW, I use the first version of MC, that's why I'm also using Ca-Mg and Espom salts. Plan to add Bud Explosion once the symptoms stop spreading completely and I see a better green. Could not enough P or K be causing this too?

That's part of why I suggested to lose the Ca-Mg, and up the MC - ... there's a fairly fine line between too little Ca/Mg and too much... Ca in particular is a major player in the uptake and metabolism in other nutrients, but too much of either can mess with the uptake of other cations, even if no "toxicity" symptoms are presented... Plants can suffer negative impacts of nute defc.'s long before they show in leaves, and the real task is to untangle the causes behind what's causing them!

 

[Simplicio]

That's part of why I suggested to lose the Ca-Mg, and up the MC - ... there's a fairly fine line between too little Ca/Mg and too much... Ca in particular is a major player in the uptake and metabolism in other nutrients, but too much of either can mess with the uptake of other cations, even if no "toxicity" symptoms are presented... Plants can suffer negative impacts of nute defc.'s long before they show in leaves, and the real task is to untangle the causes behind what's causing them!

That's part of why I suggested to lose the Ca-Mg, and up the MC - ... there's a fairly fine line between too little Ca/Mg and too much... Ca in particular is a major player in the uptake and metabolism in other nutrients, but too much of either can mess with the uptake of other cations, even if no "toxicity" symptoms are presented... Plants can suffer negative impacts of nute defc.'s long before they show in leaves, and the real task is to untangle the causes behind what's causing them!

You and the article I referenced disagree.
I strongly believe that chasing deficiencies is a fool's errand, when all that's needed is to use the fertilizer and light correctly.
I believe this strongly enough to question even your opinion, which I know gets a lot of respect here.
I'm not intending to piss in any communal punch bowl.

Here's the bio of the article's author.

We probably agree that CalMag can be a problem because the fertilizer companies don't know what kind of water we'll use.
Any fertilizer company whose fertilizer produces consistent deficiencies will quickly go out of business.

I gave the Occam's razor advice that has worked for me in the past.
The only way to know for sure what's wrong is trial and error, which trumps all else.

 

[St. Tom]

That's part of why I suggested to lose the Ca-Mg, and up the MC - ... there's a fairly fine line between too little Ca/Mg and too much... Ca in particular is a major player in the uptake and metabolism in other nutrients, but too much of either can mess with the uptake of other cations, even if no "toxicity" symptoms are presented... Plants can suffer negative impacts of nute defc.'s long before they show in leaves, and the real task is to untangle the causes behind what's causing them!

there aren't many people whos advice i would take before yours @Waira in fact there aren't any

 

[Mañ'O'Green]

The fact that the funny looking leaves are on top is evidence of light burn.
There should be no deficiencies when correctly using any good fertilizer, especially MC.

My guess is that they need more food for the present light distance, and lack of chlorophyll is allowing light burn.
I've had similar things happen, and giving more food, while temporarily moving lights away seemed to work.

We'd all be better off if those deficiency charts disappeared, because they distract us from what's really happening.
Not to mention that leaf appearance cannot be used to identify deficiencies, according to

Can Leaves be Used to Identify Nutrient Deficiencies? - Garden Myths

Nutrient deficiencies in the soil do affect plants. Can the physical characteristics of the leaves help identify nutrient deficiencies in the soil?

www.gardenmyths.com

No That is not light burn. It looks to be immobile nutrients since it is presenting in the top of the plant. I would up the MC since 350 PPMs is too low in hydro. I am running ~ 600 PPMs (not counting your starting water PPM) with good results but I always seem to get 1 pheno or plant that just does not like the same level as the other plants on the same reservoir. I am beginning to think that even with pressure compensating drip emitters that one plant is not getting its share of fertigation. I already made a new manifold for the next grow.

Diagnostics without tissue sampling is challenging at best. I have 50 years (4 years commercially growing organic vegetables and flowers) of gardening under my belt and the last 5 years I have been growing cannabis indoors hydroponically. I know a lot about farming and I have learned from and defer to @Waira when it comes to a tricky cannabis diagnosis. You would be wise to learn from him.

 

[Proph]

You and the article I referenced disagree.
I strongly believe that chasing deficiencies is a fool's errand, when all that's needed is to use the fertilizer and light correctly.
I believe this strongly enough to question even your opinion, which I know gets a lot of respect here.
I'm not intending to piss in any communal punch bowl.

Here's the bio of the article's author.
View attachment 1169412

We probably agree that CalMag can be a problem because the fertilizer companies don't know what kind of water we'll use.
Any fertilizer company whose fertilizer produces consistent deficiencies will quickly go out of business.

I gave the Occam's razor advice that has worked for me in the past.
The only way to know for sure what's wrong is trial and error, which trumps all else.

Wait.. So deficiencies are the FERTILIZERS fault? Not the grower, not the ph, not the plant, not over or under feeding? If a plant is deficient, it means the fertilizer was lacking?

I read the entire article. It was very misleading. It says that the deficiency memes don't work because most people just look at the image and dont read the part about all of the other possibilities.. Then it says that the ONLY way to diagnose a PLANT deficiency, is to send the soil off to a lab for testing, lol. Then you say that the only way to know is " trail and error".. So which one of those three is correct? Is trial and error the only way to know like you say? Or is a soil test the only way to know like the article says? Or is it the fertilizers fault as you've also said? Please clarify.