Hey everyone! Looking for some help with my plant on my first grow. Currently in flower and have noticed these small brown spots appear. I have 3 plants and only 1 is affected, all fed the same. Feeding them Canna Coco AB with PK13/14 during the previous week. Any advice is greatly appreciated.
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Looks like calcium deficiency. The curling leaves look like heat or light intensity.
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Thanks for the fast reply! Ill grab some calmag after work and see how she responds
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Back your lights off a bit too. Put your hand under the lights at the canopy. If it gets too warm after a min, imagine what the tops of your plants are feeling. Just a few inches will help
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I’d bet you could just up part a or b which ever contains calcium… but if that part has higher nitrogen with the calcium it might be worth looking into something like calmag. Looks like you are using plenty of nitrogen. Or if you are using RO currently you could try dechlorinated tap instead. Usually tap has a lot of calcium.
I tried looking up labels for your nutrient line without any luck. 
Im currently using dechlorinated tap water, i will check when i get home which part has the calcium. I will back the lights off, could that also cause brown spots or just the curling?
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That’s some excellent advice those two gave you!!
Cannabis uses a lot of calcium during stretch and it looks like you’re almost out of stretch now and I wouldn’t be surprised if it used more than supplied.
Turn the lights down and let them rest and focus on repair for a couple days.
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…or wind burn. Is that leaf near the fan?
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I mean yeah. If your lights are really intense it could increase demand for nutrients. but at that point you would see bleaching and or burning soon after. This is where co2 talk comes in.
I’m assuming your pH is in proper range?
This is also a thought
This plant is on the opposite side to the fan so gets hit the least. I will start supplementing some extra calcium starting this afternoon and also back the lights off abit. I was having issues with pH for the first few weeks due to faulty equipment but pH has been fed at 6 for the last few weeks
Just make sure you check all other possibilities before supplementing. You very well could have another issue.
This is good observation. I was scrolling to suggest ditching the pk 13/14, I couldn’t be successful with it any way i tried.
If OP has it, I would also include cannaboost and rhizo. Imo there is not a lot of reasons to use canna nutrients without the boost.
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What do you mean by you couldnt be successful with it? I do not have canna boost as i was trying to keep it abit more simple for my first grow and have read alot of people having great success with just the canna ab alone
I have started dosing some calmag to my regular feeding and have turned the light intensity down. I had someone comment it could be possible boron or phosphorous deficiency. What is everyone else’s thought?
I couldn’t find a place to apply it and be successful. Maybe the concentrations are too high or whatever, I’m not really sure. I thought the canna base nutrients were pretty good and rhizo + boost complimented the base nutrients well. Ut the pk 13/14 just seemed like an unnecessary product. Which would fall in line with your research on use A/B.
You don’t have a Boron deficiency. If I knew nothing about this I would say you’re maybe letting your coco get too dry or not feeding frequently enough. But you posted the use of pk 13/14 has me thinking maybe its possible you have nutrients built up and locking out others. What does your ph and ppm in vs out look like? And how often are you feeding?
I was feeding once per day to 30% runoff until 4-5 days ago i started twice per day as theyve been drinking alot more lately. I just fed 1350ec @ 5.85 ph and runoff was 1300ec @ 6.15 ph.
This sounds like you were doing right. Are you feeding right at lights on and then 6-8 hours later?
Just remember that, new growth will reflect healthy leaves if it was CalMag, but old leaves will remain the same. Try incorporating Calmag into your normal watering cycle, perhaps every other watering.
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Lights turn off from 12pm-4pm. Ive always fed when i get home around 5pm but have started feeding before work around 6-7am.