I think I have a calcium problem

Hi all,

I am a new cannabis grower. The last time I did grow was 30 years ago. I am a pretty experienced with hydroponics since I have been growing other things that way casually for about 20 years. The grow thus far has been very good. I have gone light on the nutrients to date and I think that is the source of the problem. The details of the grow are:

Strain: WWA
Method: hydro - autopot (first time using this particular method)
medium: coco
Nutrients: General Hydroponics Flora
TDS: 900-1000
PH: 6
Temp: 74-79
RH: 60-70%
Light: HLG 300L V2 RSpec
Tent: 3x3 Secret Jardin Dark Room
Ventilation: AC Infinity 4"
Planted on 7/8 (germinated in 2 days!)
Flowering for roughly 2 weeks. They are roughly 3 ft tall

Now for the pics:




It looks and sounds like a calcium deficiency. Those spots have just started showing up in the past couple of days. Any thoughts would be greatly appreciated including the best method of getting them healthy again.

Thanks

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Does look like some calcium deficiency,how much calmag are you feeding?and how often?
Also your leaves are looking slight light green.
Let me tag some vets and see what they say.
@Myfriendis410 @dbrn32

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Thanks for your help. No calmag has been added. The light green to some degree are an artifact of the pictures but they are lighter than I would anticipate. I just got back from a 3 day business trip. They appear a little lighter green than they were before I left. I did add 10 gallons of water/nutes last Sunday.

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You definitely need to add calmag in to the mix when using GH flora,
Are you following the GH flora series watering schedule?
In the their schedule there is calimag added on every feed.

Sorry picture is horrible
But if you go on there site and check out their feeding schedule you are supposed to add calimag every feed and watering.

Thanks for pointing out about the calmag. I was following the feeding schedule outlined in the ILGM guide. I figured it was more specific to cannabis while the GH schedule (perhaps) is a general recommendation. I knew that the Flora Micro had ~%5 calcium so I thought that was adequate. Does it matter the brand of calcium/magnesium used? I know that GH sells CalMagic which I would assume the appropriate supplement. The strange thing is that the GH feeding schedule that I was looking at does not mention calcium supplementation as far as I have seen. I was using this.

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I figured out my problem. I was only looking at the 3 part chart not the 6 or 10 part chart that include supplements as well. I guess it pays to read the FAQs. Thanks for the heads up!

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That was my next question
Are you using the 3 part?
6 part ?
Or 10 part?
Either way I would be adding at least 3ml of calimag.
GH calimag is good or any other brand I’m sure won’t hurt.

Moving forward, I am going to start with the 6 part and see how that goes. What are your thoughts on the leaf color of light green? Nitrogen deficiency?

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I am definitely no expert or even qualified to give you an answer lol but in my experience and what I have seen and read YES it looks like nitrogen but let me see if @imSICKkid @AfgVet are around and they will give you a more accurate answer.

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I would agree. Cal/mag is needed. Flower stage is where you see the issues.

Not sure what you feeding schedule is like. Are you feeding everyday? If so, add the cal/mag to your nutes. If not feeding every day and you have a water only day, add the cal/mag to that.

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Thanks @AfgVet . Since I am using 12 gallon autopots, my feeding schedule is roughly weekly refill of the reservoir. It usually takes about 5 to 7 days to drink 12 gallons. I was going to pick some cal/mag up over lunch and add it to the reservoir today at normal strength. Does that sound correct? Also, do you think that the leaf color is a little light? I will say that the last photo that is zoomed out has a more realistic color to it. The close ups always seem a little lighter than they really are.

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I also concur…Cal-mag deficiency. :+1::+1::+1:

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If you already have nutrients mixed in the reservoir I would toss and make a new batch.
You can’t add calmag after you have added your nutrients.
Calmag and amori si should always be added first.

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Thanks @Sincitytoker @MrPeat @AfgVet . You are awesome!

Current nutes are going to the tomatoes and peppers. I will reload with the calmag and other supplements and nutrients for the good stuff.

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@not_sure
Anytime!!!
Good luck and happy growing
:+1::ok_hand::call_me_hand::dash:

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