Calcium Deficiency? Opinions Wanted!

[Logan Burke]

I'm growing in 5 gallon DWC buckets under a 315w cmh light, using Floranova Grow/Bloom, along with GH Calimagic as needed. My plant's are just over 4 weeks old, and about 1 week ago they began to hit a very serious snag. My PH initally was kept at 5.8, but since the appearance of these symptoms I've raised it to 6.2 to aid in calcium and magnesium uptake, while adding app. 150ppm (.500 scale) of CaliMagic. This seemed to slow the progression, but symptoms are still spreading across all 4 plants. Anyone have any ideas here? It started with those bottom leaves, but has very quickly begun spreading to the leaf tips of my top fan leaves, as you can see them starting to curl upwards. Temps: 69F night/75-78F daytime.
The strain is White Rhino, RO water, and I'm giving between 1 and 2mL a gallon of Floranova Grow (adds up to about 150-200ppms at a .500 scale. Am I simply not giving enough base nutrient, or should I increase the Calimagic to the full strength dose of almost 4mL a gal?

 

[hotrodharley]

They seem fairly light in color so doubt it’s had too much of anything. I would increase the cal mag as well as the other two by about half and watch.

 

[Logan Burke]

Ok I much appreciate it Harley! I also felt like overferting was unlikely, the ph and ppm is totally stable, neither of them move at all on a daily basis. If I don't reign this issue in soon, my baby's will be in rough shape! Those pics were from yesterday, here are today's if it is of any help. Progression doesn't seem to be at all slowed by yesterday's rise in ppm's, so I'll take your advice and bump the overall ppm's from 300-400 to about 500 if that sounds about right to you for their stage of growth?

 

[smtent]

Ok I much appreciate it Harley! I also felt like overferting was unlikely, the ph and ppm is totally stable, neither of them move at all on a daily basis. If I don't reign this issue in soon, my baby's will be in rough shape! Those pics were from yesterday, here are today's if it is of any help. Progression doesn't seem to be at all slowed by yesterday's rise in ppm's, so I'll take your advice and bump the overall ppm's from 300-400 to about 500 if that sounds about right to you for their stage of growth?
View attachment 4342015

I grow in a basic hydro with clay balls similar to what you have there, and I have had quite a few problems like this. I have pretty good water so typically I don't need to adjust my ph (translation I always over do it with the additives so I stopped). My first several grows went really smoothly I used the GH line. Then I started adding Cal Mag and that helps wonderfully. I also started adding Nitrogen, and I switched to House and Garden, which has been great. What has always caused the yellowing and "the Claw", which it looks like what you have starting to go on there is actually to much Fertilizer. Every time I have had this problem the solution ended up being me using less. I just plain cut the dosage in half and they come back around. Once the leaves have burned they don't come back but any new growth should be healthy. I have found they respond to the cutting back the dosage real well and when they have stabilized I start bumping things up if they seem under fertilized. I have never grown the Rhino but it looks like a good Indica strain.

 

[Logan Burke]

Yes part of the issue is that I've in the past grown almost entirely very hybridized strains, and/or autoflowers. This is one of the first close to 100% indica strain I've ever grown, and it's eating habits are just plain out different than what I'm used too. As much as HotRodHarley made sense in his post, I do hear what you are saying. I'm really not getting much yellowing but for the center of the large brown spots, but you say that these symptoms are very close to the ones you encountered? During my last grow with Snow White, as a small seedling, she began getting spots very similar to these when I started feeding a higher nute level. So what you're saying does kind of make sense, as all I've tried so far is upping the nutes. I'm going to give HotRodHarley's advice a swirl, but if the issue worsens or at least doesn't start spreading at a declined rate, I'll give your advice a try. Do you think simply adding water to my buckets to reduce the ppm's will be sufficient, or do you think a full-on res change is necessary? PH/PPM is totally stable, and I tend to avoid res changes unless there is instability. Sorry for my rambling, I just try to provide as much info as possible as I know a lack of info is so very frustrating!

 

[JohnDee]

Hi Logan,
I very recently had a couple of plants show similar leaf damage. This was in coco and fairly young plants like yours. Turned out to be salt build-up in the coco. Not enough runoff. Is that a recirculating system? Could it be that you have something similar. Excess nute build-up can lockout other individual nutrients...so that might explain why they aren't darker. I've had that happen with a Waterfarm.

The other possibility...as Harley suggested, is that your strain is a serious nute hog. And along those lines White strains derived from White Widow are all in need of serious Mg supplementation. Family trait. So if everything looks ok down below ...a bump in nutes may be needed.

Sorry to confuse things by not having a strong opinion...but hopefully the info may help.
JD

 

[JohnDee]

...he's back. OK this shot is a young plant in coco almost finished with training. Leaf on lower left is clearly from not enough nutes/mg. But the other problem plants from salt build-up started with burned tips and then a mottled brown over the whole leaf.
JD

 

[Logan Burke]

Hi Logan,
I very recently had a couple of plants show similar leaf damage. This was in coco and fairly young plants like yours. Turned out to be salt build-up in the coco. Not enough runoff. Is that a recirculating system? Could it be that you have something similar. Excess nute build-up can lockout other individual nutrients...so that might explain why they aren't darker. I've had that happen with a Waterfarm.

The other possibility...as Harley suggested, is that your strain is a serious nute hog. And along those lines White strains derived from White Widow are all in need of serious Mg supplementation. Family trait. So if everything looks ok down below ...a bump in nutes may be needed.

Sorry to confuse things by not having a strong opinion...but hopefully the info may help.
JD

I'm open to any and all suggestions at this point, as I feel like I'm learning how to grow all over again lol so I very much appreciate your input! I run standalone DWC buckets, so I don't think that there is nute build up. Maybe that could happen with the hydroton, I may as well flush their netpots just to be double sure that this isn't a problem. I generally don't go over 300-400ppm's for plants this age, so I'm weary of increasing the nutes, but I really don't have much a choice as these babies won't have long left if these symptoms don't slow down! So my plan is to up the CalMag to 3.5mL-4mL/gallon, and increase the ppm's from my base nutrient from 150-200 to 300-400, adding up to a grand total of (estimated) of about 600-700ppm's. Although that sounds really high to me, I have faith in your guys's advice! I can always reduce them if I see nute burn!

 

[Logan Burke]

Do you guys feel like this is a more Mg related issue, or at least at the core of the problem, rather than Ca? I'm tempted to foliar feed some CaliMagic, but if my girls are really just deficient of Mg I would rather foliar with Epsom Salts as not to overload her in combo with the increase in Calimagic. Again, I cannot thank you all enough for replying!

 

[Aussieaceae]

Hi Logan, have you checked your ph metre is properly calibrated?

 

[JohnDee]

I can always reduce them if I see nute burn!

You could bump it up in two steps if you're nervous. That's what we tell nubes all the time...ease into it.

And I wouldn't worry about flushing the hydroton. If you are getting a ph reading from a solid bucket sample...then that's your number.

When my Waterfarm unit got toxified...I was just putting in correct solution but not checking the actual bucket ph. Had nothing to do wityh the hydroton. Nube mistake...
Good luck dude...
JD

 

[Logan Burke]

Yes, at first that was suspect for me. But it is right on point with monthly cleaning and calibration.

You could bump it up in two steps if you're nervous. That's what we tell nubes all the time...ease into it.

And I wouldn't worry about flushing the hydroton. If you are getting a ph reading from a solid bucket samle...then that's your number.

When my Waterfarm unit got toxified...I was just putting in correct solution but not checking the actual bucket ph. Had nothing to do wityh the hydroton. Nube mistake...
Good luck dude...
JD

Sounds like I've got a game plan then. It's interesting how different genetics have reduced me to a complete newb again haha, but I'll keep plugging at it I'm feeling good about this plan. I'll keep everyone posted on what approach resolves the problem.

 

[Aussieaceae]

Yes, at first that was suspect for me. But it is right on point with monthly cleaning and calibration.

Sounds like I've got a game plan then. It's interesting how different genetics have reduced me to a complete newb again haha, but I'll keep plugging at it I'm feeling good about this plan. I'll keep everyone posted on what approach resolves the problem.

Understood, and i hear you. Might be worth a quick calibration imo, just to have all bases covered, stranger things have happened.

I've had plants look just like this in a waterfarm, ph was too low, well under 5.5.

 

[Logan Burke]

Understood, and i hear you. Might be worth a quick calibration imo, just to have all bases covered, stranger things have happened.

I've had plants look just like this in a waterfarm, ph was too low, well under 5.5.

Ok I've now got my ph meter recalibrated, it was off by .1 on the 7.0&5.0 cal so I'm sure my PH was closer to 6.0 rather than 6.2 which I'm sure didn't help the issue.

As for an update, I've got good news! After increasing the overall ppm's to 580-600 on all plants, the symptoms have spread by only a very small margin of what they were when I was in the low 400 ppm's. I'm not quite at the point of declaring it a solved case, but I think we've definitely gotten to the core of the problem, as Dee and Harley suggested, underfeeding I think just in general, but most definitely of the CalMag. I've also switched as of yesterday to using the Floranova Bloom full cycle which is essentially the Lucas Formula in a bottle. It has slightly more Magnesium, about 20-30% more than the Floranova Grow did, which may also be helping stop the spread of symptoms. I'll post back in a few days when I get the symptoms to completely cease spreading just in case future growers run into this problem.
Appreciate all of my RIU family for helping, y'all rock!

 

[JohnDee]

Hi Logan,
Glad things are looking up...or slowing down. On some of my plants in training...everything can look perfect, except for 1 or 2 leaves. Stress I guess...definitely stress on me. lol

It was sort of odd that Ca wasn't ever discussed. But that's almost always brown spots. Whereas your leaves had a general fading. Plus you're giving calmag.

So before this, it was autos only? No wonder you're out of your element. I've never grown them nut I ubnderstand they are very different.
Cheers,
JD

 

[Logan Burke]

Hi Logan,
Glad things are looking up...or slowing down. On some of my plants in training...everything can look perfect, except for 1 or 2 leaves. Stress I guess...definitely stress on me. lol

It was sort of odd that Ca wasn't ever discussed. But that's almost always brown spots. Whereas your leaves had a general fading. Plus you're giving calmag.

So before this, it was autos only? No wonder you're out of your element. I've never grown them nut I ubnderstand they are very different.
Cheers,
JD

Haha I can understand that, as much joy as they bring me they can bring two-fold as much stress when things are going bad! I agree, Ca was my first thought, but with the addition of calmag not slowing it down all that much it was freaking me out, I generally use the RIU help section as my last resort. And yes in four/five years of DWC it was always autoflowering strains, I thought "How different could photo's be? They're still cannabis". Boy did that attitude come back to bite me, haha. I'm used to having to tip-toe my plants up in nutrient dosage, whereas these photo's are already going deficient by the time I tip-toed the dosage up high enough. But they're still alive and I've learnt some more, so I'm happy! Giving a try at ScROGing this grow as well, so this grow will have a few 1st's for me.

 

[Unorthodoxy]

Hi Logan,
I very recently had a couple of plants show similar leaf damage. This was in coco and fairly young plants like yours. Turned out to be salt build-up in the coco. Not enough runoff. Is that a recirculating system? Could it be that you have something similar. Excess nute build-up can lockout other individual nutrients...so that might explain why they aren't darker. I've had that happen with a Waterfarm.

The other possibility...as Harley suggested, is that your strain is a serious nute hog. And along those lines White strains derived from White Widow are all in need of serious Mg supplementation. Family trait. So if everything looks ok down below ...a bump in nutes may be needed.

Sorry to confuse things by not having a strong opinion...but hopefully the info may help.
JD

I have a White Widow auto that is the heaviest feeder among 5 strains I'm currently growing. I just bumped up the cal mag from 5ml to 10ml, and that's with 6g per Gallon of MegaCrop. I would bump up the MC again too, but I think it's time to start flushing.

This comment was really helpful in my particular situation. It kind of confirms what I thought I was seeing.

I think I want to try some Epsom foliar feeding, and a search for information led me here.

This is my first grow. Going to harvest my first plants in a couple weeks, I think, and overall it's looking really good! I have a grow thread, but it needs serious updating.

 

[Logan Burke]

Oh wow Unorthodoxy! That's a pretty crazy high dosage a calmag you've got going there, prior to this event happening to me I'm not sure that I would've believed that a plant could tolerate so much Calmag. But now I know otherwise, haha. I'm happy that this thread helped you!

On a seperate note, I've upped my ppm's up to 700 as of now, with 3.5-4mL/gallon accounting for nearly half of the overall ppm's, and my babies are STILL showing some very minor symptom progression. It isn't anywhere close to as bad as it has been though of course. So, I'm thinking that I should bump the CaliMagic on up to 5mL a gallon, and not add more base nutes? Would you agree, @JohnDee ? Or increase the base nutes alongside the CaliMagic dosage?

 

[JohnDee]

So, I'm thinking that I should bump the CaliMagic on up to 5mL a gallon, and not add more base nutes?

I'd vote for that. Just bumping up calmag. I've seen guys use as much as 2tsp/gal Epsom Salts but not with calmag. But some strains/phenos really need the Mg bump. Like Unorthodoxy experienced.
JD

 

[Logan Burke]

Do you guys think that it would be ok to foliar spray my plants with the Calimagic, even though I'm feeding it to the roots already? Don't want to lock anything out. The symptoms are spreading much slower than when I started this thread, it is just going to take me some time to dial in the optimal dosage, and until then I'm hoping that I can avoid losing more fan leaves by foliar feeding a bit.
Much thanks!