What Dificiency is this ?

I have been sifting through pictures on the internet and reading threads trying to figure out what is wrong with my leaves. I have been using Veg+Bloom for RO/Soft, with Botanicare Cal-Mag (Growing in Canna Coco medium). I am in about the 3rd week of veg and my plants were doing fine. I just watered them lastnight and when I woke up this morning I discovered that my leaves were drooping down and had these black spots on them.

Calcium def is the spotting. The interveinal chlorosis is magnesium def. Looks likes you might need to add more calmag to.your RO. Some types of coco need to be charged before use...

Cocos great but its made of three grades of material, one of which tends to hold on to calcium. Sorry I cant remember all three correct terms for each grade, one is pith though.
Make sure your PH is correct for soilless mediums or that can make it harder to absorb Cal too.
I don't have many cal mag issues and have grown coco for a while, but I use tap water and its hard water so I assume the high levels helps me out some. I do still add cal/mag a few times per grow though.

@a senile fungus Thank you for replying! how would you recommend I fix this problem ? Here is what I have been doing: I take 10Gallons of RO but before I add my Veg+Bloom to my RO I raise my EC with Cal-Mag to .2 or 100ppm which is about 12mil or 1.2ml per gal. I then add Veg+bloom at 5grams per gal which brings me to a total of 50grams. I then add more Cal+Mag 18mil which brings the total of Cal-Mag added to 3mil per gal which is Bontanicares lowest recommended dose.

Homegrownx said:

@a senile fungus Thank you for replying! how would you recommend I fix this problem ? Here is what I have been doing: I take 10Gallons of RO but before I add my Veg+Bloom to my RO I raise my EC with Cal-Mag to .2 or 100ppm which is about 12mil or 1.2ml per gal. I then add Veg+bloom at 5grams per gal which brings me to a total of 50grams. I then add more Cal+Mag 18mil which brings the total of Cal-Mag added to 3mil per gal which is Bontanicares lowest recommended dose.

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How bad is the rest of the plant? I would increase your calmag. I'm on well water r and my big plants get closer to 5mL/gal.

My next soil mix I'll try adding more oyster shell meal and mag sulfate...

@a senile fungus @coreywebster I forgot to mention I always keep my Ph at 5.9 and I am using Canna Coco

I let mine swing from 5.5-6.2 because there is no perfect ph point in coco where all nutrients are optimally absorbed.



On this chart you can see what I mean on the hydro side.
Its a bastard though, many charts show slightly different.
Regardless I let mine swing a little, I have heard of people who don't though.
Edit I also use Canna Coco

@a senile fungus each of my plants are only showing symptoms on just a few of my leaves Since I just watered them would you recommend that I foliar spray with cal-mag to make up for the lack of cal-mag at the roots?

Homegrownx said:

@a senile fungus each of my plants are only showing symptoms on just a few of my leaves Since I just watered them would you recommend that I foliar spray with cal-mag to make up for the lack of cal-mag at the roots?

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Let your pH swing, it's healthy.

I've never foliar sprayed anything, can't help you there. I don't see how it can hurt, just don't overdo it LOL

coreywebster said:

I let mine swing from 5.5-6.2 because there is no perfect ph point in coco where all nutrients are optimally absorbed.

On this chart you can see what I mean on the hydro side.
Its a bastard though, many charts show slightly different.
Regardless I let mine swing a little, I have heard of people who don't though.
Edit I also use Canna Coco

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It looks like by doing 5.9 consistently I have been locking out Calcium to my plants. Would you recommend I lower my ph next feeding? also when it comes to foliar spraying do you ph the solution?

Homegrownx said:

It looks like by doing 5.9 consistently I have been locking out Calcium to my plants. Would you recommend I lower my ph next feeding? also when it comes to foliar spraying do you ph the solution?

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I'm the same as ASF above, I don't really foliar spray but I don't think PH is as important when doing so because that's for root uptake rather than foliar.
I would lower the PH next water yes. You will know the problem is solved when it stops getting worse. It wont make the damaged leaves healthy again but you new growth will be better.

@a senile fungus @coreywebster thank you guys for all your help!

Homegrownx said:

@a senile fungus @coreywebster thank you guys for all your help!

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Update the thread in a few days, so people looking at this thread in the future have a more complete documentation for their own research. If it gets better, post a pic.

Thanks and happy growing!

@a senile fungus great idea! I will forsure keep this thread updated! Thank you for all your help ! I took some more pictures of the affected leaves that were on different plants. I went ahead a defoliated the affected leaves. Now I'm just trying to decide if its a Calcium deficiency or Calcium lock out? I'm going to try a slurry test on the coco from my pots. Whats your opinions on these pics ?

@coreywebster @a senile fungus I just did a slurry test on my coco and it's reading at 6.3. Is this high Ph locking out my nutrients ?

Possibly. I would just do as you were going to and water with the lower end of the coco ph scale for the next few waterings. Coco is self buffering but you may have some build up from previous feeds at that constant ph of 5.9 you were using. Make sure you allowing a reasonable run off each watering too. You could give them a good flush with plain ph 5.5 water if you want. Its coco it drains well.