Light bleaching? Deficiencies? Or just Noobness?

Wasn't sure where to post this...But I'm pretty sure it's light bleaching so my home here in LED seemed fit!
Here's a look



My cxb3070s @1.4A are positioned pretty much directly above the 4 mt cooks in the corners of the tent. Cobs have been 10-12 inches away and haven't been moved for a couple weeks now. You can tell the mt cooks are limey looking compared to the CSSH in the middle. There are brown spots starting to form on the upper 30% of leaves on all 4 cooks. There is also burning on the edges of some of the leaves closest to the tops. I noticed these symptoms 5 days ago. All of them (limey, brown spots, slight burn) have slowly progressed since. These pics are from today, day 39 flowering.

All 5 have the same soil mix:
Roots B2 as base
Oly mountain fish compost
Worm power ewc
Extra perlite

Kelp, crab, and neem meal
Oyster shell, glacial rock dust, little bit of azomite

The CSSH is in 3gal, the others in 1.5
Throughout flowering they haven't had much else but plain bubbled tap, silica/aloe here and there, couple basic teas.
After first noticing the symptoms I gave them a tm7 watering with aloe and silica. The soil was super wet at the time already so between the 5 they only drank about a liter at most of that mix. Two days later, I top dressed lightly with fish bone meal, kelp, alfalfa, and ewc. This mix was watered in with a barley sst.
The spots have progressed to more leaves and are getting darker, the overall color of the plant seems pretty limey to me now. It has definitely been a slow progression, but a progression nonetheless.

I raised the lights about an inch... Idk what else to do. This is my first grow and every little thing that comes up I do crazy amounts of research on. From what I've gathered I'm probably just overthinking stuff though. Plain water will get me through harvest, and the changing of the leaves are completely natural this late in flowering. Topdress a little more ewc possibly, and stop worrying so much. Also next time, use two 15 gal smart pots instead of multiple smaller ones. Right?

Much Love

Looks like ca (brown specks) and mg (yellowing between veins) deficiencies. Add some gypsum (1g = 60ppm Ca) and epsom salt (1g = 26ppm Mg). Say, 2g of each. That's a good ratio of ca:mg.

I think I have those numbers right. (I'm lousy at this stuff.).

az2000 said:

Looks like ca (brown specks) and mg (yellowing between veins) deficiencies. Add some gypsum (1g = 60ppm Ca) and epsom salt (1g = 26ppm Mg). Say, 2g of each. That's a good ratio of ca:mg.

I think I have those numbers right. (I'm lousy at this stuff.).

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Thanks! Those are the deficiencies that made the most sense to me. I have super hard tap water and I was half assuming I would not need to add anything in too often. Any alternatives to gypsum? I have oyster shell. Hard to find gypsum in small quantities like I need it.

Great avatar btw. Braddah IZ

I can't think of anything fast acting. You'd spend less on a bag of gypsum than you would on a calmag product.

The mg looks like the serious problem. The ca doesn't look too bad. Maybe there is a ratio problem and adding mg would fix the ca too.

You can prepare for the future by dissolving some eggshells in vinegar to create calcium acetate. After you let it evaporate, 1g of that is 60ppm in a gallon. (I should have mentioned above, I referred to g/gal.). I believe that's immediately available to the plant.

I'll do an epsom watering tomorrow morning. If no good progress after two days I'll grab some gypsum and give her a whirl.
Thank you for the quick responses.

Waiks said:

I'll do an epsom watering tomorrow morning.

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BTW: Normally I'd recommend 3/4tsp/gal (or 1tsp) for that level of deficiency. 1 tsp of epsom is 5.2g. So, that's about 240-300ppm (if I'm doing the numbers right). I only mentioned the g=ppm numbers because I was thinking how you'd use two products together, their ratio.

Not sure what Roots B2 is... I'm guessing peat or something like a sunshine mix. You mixed up the soil right so we know the nutrients are in there, they just need to be made available if a plant is deficient.

I think you mentioned mites before and the pictures don't look unlike a spinosad battle with mites. They aren't easy to get rid of, I can say that much. Either way I hope you get it sorted out~

I think they are just hungry in general and calmag shows up because cal is immobile. It makes sense, the plant in the center is in 3 gal and the hungrier ones are in 1.5 gal. If it were earlier I would bubble a strong nutrient tea to let the nutes break down in the tea and then water it in so the plant can take it right up. BUT it may be too late in the cycle to do much about it so no worries, I would just let them cruise to the finish and they might turn out better than if you try to address it so late in flower. Epsom salt for example is water soluble so it spikes PPM and could lock out other salts, potentially making the problem worse and potentially affecting smoothness of the smoke.

The best action might be to mix the soil with more fertility for next run. For every liter of spent soil I add 6ml of chicken manure from organic certified layer hens to boost soil fertility to carry the plants all the way through veg and flower under high PPFD. The recipe I am currently experimenting with:

Fresh EWC/vermicompost 20ml/L
Organic chicken manure and/or Pure 6ml/L
Azomite/Glacial Rock Dust/Basalt 2ml/L
Organic Kelp Meal 1ml/L
Organic Crab Shell Meal 1ml/L
Organic Alfalfa Meal 1ml/L
Organic Neem Meal .5ml/L
Organic Fish Bone Meal .5ml/L
Indo Guano .5ml/L
Greensand .5ml/L

Roots B2: Peat Moss, Coco Fiber, Perlite, Pumice, Worm Castings, Calcitic Lime and Dolomitic Lime for pH Control, and Rock Dust

Yes, yes, yes.
The plants have been in the 1.5s for almost two months now. Vegged in there a bit. Definitely doing 2x 10# or 15# smarties next round. Blumats too.

I think I'm going to get a compost tea started right now and hit em with that instead of the epsom. I know they've probably used up a lot of what's in the soil already, but like you said, it's pretty late in flower. I have been letting the soil dry a little between waterings in fear of overwatering... Could that have caused the nutrients to be less available? Microbes dying off and whatnot

Thanks again everyone!

Waiks said:

Thanks! Those are the deficiencies that made the most sense to me. I have super hard tap water and I was half assuming I would not need to add anything in too often. Any alternatives to gypsum? I have oyster shell. Hard to find gypsum in small quantities like I need it.

Great avatar btw. Braddah IZ

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what TDS is your water at? if it's above 300, that's your culprit== lock out. adding more cal/mag will compound the problem. A RO flush would be a quick/inexpensive(store jug) test to confirm.....

good luck

I can't believe the op is getting away from what was recommended in post #2, #4, #6. Dude needs to make it to harvest at this point. Nothing is going to get lush and perfect, but it could get better a bit and mag sulphate might help.

COBs + Organic soil can be tricky. They can put down a lot more intensity than we are used to and the plants need fertility. You can really end up chasing your tail trying to diagnose specific nutrient problems. The best solution I have ever found is to address the soil mixture before the plant is potted up into it. The second best is bubbled nutrient tea.

Not sure if epsom would help or hurt, but it sure will spike the ppm.

That roots mixture may be contributing to the problem with calicitic and dolo lime. Also it depends what you mean by letting them dry out, an LOS should always be wet but not soaked. If your media gets too dry microbes will go into a cyst form waiting for water and their time to proliferate again... Sometimes after drying out it is a pain in the ass to re-hydrate peat and if you don't make sure the media is damp all the way through, sometimes the core of your media will become dry and will stay dry after watering since the outer layer becomes hydrophobic and most water will just run off. Things like aloe or yucca will help you rehydrate dry media.

I think the emphasis needs to be made that high quality vermicast/compost is what sets an LOS apart and keeps it running. pH and all that other wacky shit won't matter once the SFW is established and healthy.

IMO, the pot size is OK, in fact I've seen bigger plants in even smaller containers.

If I were in your shoes: ACT+ful power/ back the lights off/check for mites.

I haven't been able to keep up with my CoB's (Vero29) either. But I did make it to week 9 of flower! Only have one more plain watering left. My deficiencies started a little later then yours, but i misdiagnosed mine a little.

Here is week 8 of flower on a top that seemed to have the damage slowed after heavy addition of potassium and cal/mg.



Here is now, week 9, on a top that got a little more damaged, I believe because it is located closer to an LES. You can see all the buds around them are a little crispy too.

Act is brewing atm. Girls need water right now so I will hit with a little store bought RO.

What's an inexpensive way to test my tap? I've looked up the analysis from the board and it looks fine. My building is almost 60 years old though.

Idk man, the 3 gal girl looks fine and I'm starting to think it's because I used far less rock dusts in that mix. My tap could be the culprit. My dish rack used to be black but it turns white after doing the dishes lol. Also, the 3 gal girl is far from the cones of the COBs...raising the lights more tn

Waiks said:

What's an inexpensive way to test my tap?

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PPMs? I use HM EZ-TDS. Costs about $15 US on Amazon. The TDS-3 is $25 and has automatic temp compensation (but, for what we do that's probably overkill.). You can mix 1g table salt in 1 liter pure (distilled) water to calibrate it (that's 1000ppm).

If you're in the US, your provider is required by federal law to publish an "annual water quality report." They're usually online. That may show total ppms (min/max through the year) and the makeup of those ppms. My ppms are 600-800. I mix tap with RO (filtered, from a vending machine) to get a starting 150ppm.

My guess is your main problem being lockout from too much calcium,you mixed 4 things with calcium into your base soil and that will lockout mag. I would do a heavy RO water flush and mag foliar to start.

After doing some more research based on the discussion here, I've decided to foliar mag and water reg RO. I know I need mag, but I don't want to salt up the soil.

Looks like 1/2 tsp epsom per gal water looks nice for a foliar. Wish me luck!

Big thank you to everyone

Waiks said:

Looks like 1/2 tsp epsom per gal water looks nice for a foliar. Wish me luck!

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If you haven't foliar fed before, realize you can get bud rot (especially if you're in a humid environment). Don't do it under the lights or the water droplets will act as magnifying lenses and burn the leaves.

Waiks said:

After doing some more research based on the discussion here, I've decided to foliar mag and water reg RO. I know I need mag, but I don't want to salt up the soil.

Looks like 1/2 tsp epsom per gal water looks nice for a foliar. Wish me luck!

Big thank you to everyone

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I know everyone says foliar for a fast return on epson salt. I've had good like luck with watering it in.