Assistance required, toxicity?

Are you sure there are no pests? Some of that leaf damage looks iffy.

What RH/temp are you running in these rooms?

Please perform a soil pH test and return here with the result. This could very well be a Ca+ deficiency brought on by pH issues.

What are you adding for micros? This could also be a zinc deficiency.

Is there damage to older leaves, or is this relegated to the newer growth?

Looks like classic overnute damage. Do you follow ppm/ec going in or out?

id say overnute as well.... but i agree with squigg... would love to know environment and grow factors RH temps hi and lo and shit to take pests out... that curling makes me curious....

but everything else is def burn..... you have an exact what you fed it? you doing a feed/flush/feed or feeding every water????

ahh i just saw COCO to.... so first question would be PH in and PH out....

Thanks for replies.

Rh is around 45%, temp always 78 to 80 with co2 at 1000. Week three almost of flower.

Coco feed everytime. 1.3 to 1.4 EC

Ph in is 5.8. Collective run off ph from a couple plants is 6.1

Dmg is to older leaves, guess that usually means a micro

Moved to upper leaves.. not sure what the deal is.

I see Ca- (deficiency), but that doesn't cause the leaves to curl up like that, it causes the spotting and necrosis. That kind of curling is extreme and would concern me, I would loupe it, and scope at 100x.

The older leaves vs younger leaves thing isn't to do with major vs micronutrients, it's to do with mobile vs immobile elements.
E.G. Ca is immobile, whereas Mg is mobile. Ca- appears on upper leaves, whereas Mg appears on older leaves as it's being translocated from them to new growth. The Ca- appears on upper leaves because it cannot be translocated from older plant tissues to new. Same thing with N transport.

My plants looked similar when I was over-fertilizing for a few weeks during veg. The leaf curl, yellowing, brown spots/edges. I dropped the EC to 0.8-1.0 and it went away, especially the leaf curl. I still have some damaged leaves, but nothing new is popping up.

I gave a weak solution at 0.2-0.4 EC then next watering gave them the normal 0.8-1.0. I also get around 20% run-off per irrigation and I almost never use plain water. FWIW, there in Sunshine #4.

You should check the EC of your run-off just to make sure its not overfert. With my plants the over-fert was causing an abundance of N and K which would antagonize other nutrients and basically started a chain reaction because I did it for so long, I saw deficiencies of N, P, K, Ca, Mg, and Fe. They didn't get better until I changed the nutrients from a 4-1-5 to a 3-1-2 ratio and lowered the EC. Good luck.

BCrocker said:

Thanks for replies.

Rh is around 45%, temp always 78 to 80 with co2 at 1000. Week three almost of flower.

Coco feed everytime. 1.3 to 1.4 EC

Ph in is 5.8. Collective run off ph from a couple plants is 6.1

Dmg is to older leaves, guess that usually means a micro

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Bring your RH up to above 50% until the damage has subsided.

Water in at pH 5.5 and slowly bring that up to 5.7-5.8 as your runnoff corrects.

To be clear, your runnoff should really never be too much further than 0.2 pH units away from what you are putting in or you're setting up yourself for failure by not having good control over your medium pH (which can be very useful).

I would water in 5.5 until my runoff was 5.7 and then I'd bring the pH up 1 tenth of a unit each watering after that until I got it where I wanted it (5.8 for you I'm assuming).

Edit:

For your first "shot" of pH down--simply use a mL or two of a good micro-nutrient solution. This should drop the pH significantly.

I would avoid adding any other nutrients to the mix, micros only and pH down till 5.5 .

The problem might be something else, but we want to isolate out what that is--so one thing at a time.

You didnt miss a watering did you? This can happen if you let them go dry to the point of wilting.

Thanks for the replies. No missed watertings.. I'm thinking the caretaker might have watered too often or with a wrong pH.

See pic updated.. This is almost the end of week 5 in flowering and they seem way small and underdeveloped to me.

This is a picture of the other room in the same location with same workers. Not sure wtf happened here either, way underdeveloped and weird buds. These are End of week 8 flowering!! :(

I ran these exact same plants myself and they turned out great... Something is being done there that I just can't figure out. Seems like a pH issue, meter is calibrated fine.. runoff came out this time around 5.9
I will have this checked again tomorrow.

I don't recognize your symptoms, but would like to bring up that testing the pH of runoff in coco does not represent the pH in the rootzone and is not relevant to your plants. You must take a sample, mix with distilled water, and test that to get a meaningful number.

BCrocker said:

This is a picture of the other room in the same location with same workers. Not sure wtf happened here either, way underdeveloped and weird buds. These are End of week 8 flowering!! :(

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Those look terribad for week 8.

Maybe the medium is too "fast" i.e. not holding water well enough--and they're drying out too much between waterings.

Looks to me like they've been starved.

Yes , so terribad. I will check the rootzone pH. Does the distilled water have to be a certain pH to start? or just distilled right outta the bottle + medium, shake and test?

I was almost thinking they were watered too often or too much volume... I'm not sure! Logbook says never higher than 2.0 EC, which I don't go higher than and consistantly get .9 to 1 gpw

Distilled water, for all intents and purposes, has a pH of exactly 7.0. I like to think of it as having no pH at all; whatever you put into it will dictate where it ends up. Don't try testing it first - that's bad for your probe.

BCrocker said:

Yes , so terribad. I will check the rootzone pH. Does the distilled water have to be a certain pH to start? or just distilled right outta the bottle + medium, shake and test?

I was almost thinking they were watered too often or too much volume... I'm not sure! Logbook says never higher than 2.0 EC, which I don't go higher than and consistantly get .9 to 1 gpw

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Test the pH of your water first, and take a temperature reading along with it if you can (water temp). Then do the medium test and get back to me.

cctt said:

Distilled water, for all intents and purposes, has a pH of exactly 7.0. I like to think of it as having no pH at all; whatever you put into it will dictate where it ends up. Don't try testing it first - that's bad for your probe.

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Let me correct myself before Squiggly comes back! Pure water has a pH of 7.0, but distilled water likely is not totally pure as gasses dissolve into it. This doesn't matter for testing coco, though, as there is so little buffering that it will swing wildly at the addition of any further ions.

cctt said:

Distilled water, for all intents and purposes, has a pH of exactly 7.0. I like to think of it as having no pH at all; whatever you put into it will dictate where it ends up. Don't try testing it first - that's bad for your probe.

Click to expand...

Testing the distilled water shouldn't be bad for the probe if it's done quickly.

Its bad to leave the probe for an extended period in DI water, a few seconds won't break it.

It's important to remember that pH is temperature dependent. It's also not precisely true to say that 7.0 is "no pH at all".

Especially not under the interpretation of pH as hydrogen ion potential. Water has what is known as an "autoionization constant"--it is extremely low, but even in the purest water there are hydrogen ions dissociating and hydronium ions being formed.