Week 4ish, new growth yellowing

Hey guys,
second run in 100% canna coco for me
SMALL LEAVES ON BUDS YELLOWING/CURLING
Not sure exact flower date
sealed room, 78-80 day time temp, 68 night time temp. 65-70% humidity, 900-1000 ppm co2. 1kw mh, 3kw hps, all new bulbs
distance from canopy is 18-24"


Here's a pic of half the room, the rascal OG side. One bulb is a MH and one is a HPS,just for a fun side by side comparison.



6 plants per 1kw, 3g of coco each. Vigorously rooted. Overvegged. tall plants with the bottom stripped. Half room rascal OG (showing most symptoms), and the healthier looking half is Green Ribbon (veryyy sativa)
RO water
300 ppm calmag+ (4ml-5ml per gallon, used to only go up to 100ppm,1-2ml gal, but i assumed I had a calmag problem, and upped the dose on recommendation from a lot of random forum threads)
little sm90, little drip clean
Canna A + B to get my EC to the desired point
5.8-6.1 ph
Hand fed once a day
I have irrigation in place, but yet to finish setting it up. Will most likely finish it this week and will start feeding 4-5x a day

Been running 1.0 EC for most of veg, to 1.2-1.3 EC the last few weeks.




Last week, night temps been COLD and the reservoir temperatures have been getting to 52-53 degrees. I watered with this cold water maybe one or two days. Realized its a problem, started dumping hot water from the bathtub to reach 65-70 degree water. Tub is on well water, with about .5 EC. fairy hard water. Did the hot water thing for 2 or 3 days.

Bought an aquarium heater, now I keep my water about 65-68. It DID seem the yellowing got much worse after giving them the coldcold water.

In the last 4 days, I sprayed them THOROUGHLY with epsom, again with calmag+, and yesterday with Mycotrol O in case its a BROAD MITE/RUSSET MITE problem. I will continue to spray azamax and nuke em through flower every 2-3 days to make sure and knick this in the bud if its a mite problem. I scoped some leaves yesterday and couldnt find any mites. I sprayed them twice at transition (4ish weeks ago) with forbid4f.

Yesterdays feeding was the first feeding with the properly heated water. I also upped the A+B to hit 1.6EC this time, in case the plants are hungry. My next step will be to cut the calmag to 2ml a gallon, and feed 1.6 EC again, as well as another calmag+ foliar spray. This will be to make sure my plants are not being underfed. I DO worry about overfeeding though! Hopefully this isnt an overfeeding problem, although i doubt it is. I read today, that in a higher humidity environment, plants need a higher EC as they transpire less than a low humidity environment. Also, with only 1x daily feedings, I could probably up my EC without any harm?

Plants are right about to start really stacking/swelling, so I want to keep em well fed. I'm hoping cutting the calmag to 2ml per gallon will not hurt them! It should just give more EC space for the A+B, which contains calmag already.

It's mostly the rascal OGs that are affected, the sativa green ribbons are much greener, healthier in general.


Am I going about this right, or am I fucking up somewhere??

These aren't the most severe plants, just what pics I have available. You should still be able to see the interveinal chlorosis on the new growth, as well as some twisty leaves. I can update with new pictures tonight.

Another thing, every few waterings Ill randomly add small amount of humic acid and cannazyme

Have you tested the runoff?
What kind of humic?

Runoff is similar ph and usually the same EC going out as going in, maybe 50 ppm in either direction.

I usually water with 10-20% runoff, almost every watering. This is just because I'm paranoid and dont want any salt buildup lol.

Im not sure the brand of the humic right now. It's a black bottle, with a black lid. Dont remember brand name, but ill look tonight. I use it very sparingly.

Here's 3 more pix from yesterday night. I'll snap new pix tonight.

Stop spraying your plants with pesticides! Your don't have a bug problem! If you continue to use as many foliar applications you will see rot and mold very soon. As for the light green new growth, have you noticed any difference since foliaring or feeding extra calmag? I usually cut out my calmag supplement when I flip as they don't need nearly as much in flower and my base nutes have enough. How much cal and mag are in your base nutes?

I ran 6x3gal smart pots in 70/30 coco to hydrocorn ratio. Using .1EC tap water, canna A B 2ml /gal calmag. I cut out the calmag at week 3 to no ill-effect.

How much a and b are you giving them? Are u using any bloom boosters? If you didn't notice any big difference in the appearance of the leaves a day or 2 after foliar spraying calmag then that's not your prob.

only pesticide I've sprayed in the last month was mycotrol O. It can be used in bloom, and it's a very good preventative for russet/broad mites. Was OMRI listed until a few weeks ago, lol, labeling issue. Its a bacteria i believe? And the nuke-em is just citric acid and yeast, can be sprayed till day of harvest. Azamax is also safe to use fairly late into bloom. However, I will only start aza//nukeem if somebody ID's broad mites. I took pix of the undersides of some leaves, Il post em in the morning.

There's not really any harm from spraying em with calmag or epsom. I only sprayed them once each, and sadly, the yellowing didn't seem to stop.

I'm only spraying this week/next week heavily because if I have a broad mite problem, it needs to be dealt with asap. Same if it's a deficiency/lockout. Needs to be fixed soon, and once the buds swell I won't be able to spray much.

I think it could be broad mites because the twisting of single leaflets, and phantom cal/mag deficiency. I scoped some leaves today but couldn't find anything definitive. I'll post pix of what I scoped in the morning.

About spraying- plants love it. spray em with plain water every 3 sprays and nothing accumulates on the leaves. It keeps em cleaner really. I can very easily dial the humidity down to 40% if I need to, and I have a great deal of air flow, so mold isn't really a concern. Besides, the nugs are all tiny still.

I'm not sure the exact amount of ml a+b im giving, I just give them equal parts a+b until I reach my desired EC. No boosters or additives other than sm90/dripclean and rarely humic and silica. Im unaware of the calmag ratio in cana a+b.

If its not calmag, is it perhaps P or K lockout/deficiency? I'll have to research them more in the morning.

I noticed significant growth within 24 hours after giving them yesterdays 1.6EC feeding.
I fed the plants 5.8ph 1.6 EC today, 2 days in a row with 1.6EC feeding and 65 degree water!Maybe I'll notice tomorrow if they just needed the heavier feed andd warmer water. Sadly, my co2 tank ran out so they aint gettin any co2supp today.

My next reservoir, I'll ween down to 50 or 100 ppm calmag with my RO, and then 700 ppm A + B to hit my 1.6 EC, .5ml /gal drip clean, splash sm90. I'm still skeptical of cutting out calmag. I'll take your word for it though.

Zarth and mango, are you guys both running co2? What nutes and EC do you guys feed? And what temps do you keep?

I dont know if I should keep a 78 degree daytime temp or if I should up it to 82ish just so I could utilize the co2 and higher humidity better.

Iron lockout maybe? due to the cal mag?

Also OGs can be light feeders... But it looks like nute lock to me.

And are those hairs turning already?

Yeah, the hairs on the OGs are definitely slightly turning. I think it may be from my aggressive foliar sprays this last week? I use an atomizer, lights off, high humidity, fans off, and let the foliar solution sit at least 30 minutes before I turn fans back on. It's not all the hairs, just some are starting to slowly shrivel/brown. The "outside/older" hairs. The new nuggage thats forming has explosive bright white hairs still.

I have been feeding pretty light, 1.2 EC average. They were showing these yellowing symptoms then. Problem was, .6 EC (300ppm) was calmag, and the other .6 EC was A+B. Seems out of wack; Made me think I need to up my EC and lower my calmag. Especially running 70% humidity and 1000ppm co2 in rootbound pots. This setup is meant to feed 3x daily or so, with a lower (1.0-1.2 EC). Since I'm feeding once daily, it's alright to up the EC.

Im gonna flush tonight! 68 degree water, 50 ppm calmag, .5ml /gal drip clean, and then I'll add A+B until I hit .8 EC. I'll try to flush 1g through each 3g pot and see if that helps restore my calcium/mag/p/k levels in the soil

I'll have my co2 tank back on by lights on (6 pm tonight). I'll also be able to tell if the 1.6 EC feeds the last 2 days have hurt the plants.

In my experience canna doesn't like added Cal mag as much as some other ferts I've used in coco

Even with very low ec tap / ro

My guess is K lockout due to too much Cal and mag

Also, when I used canna, calcium carbonate had more problems than Cal nitrate

It would make sense to me that canna has more Cal and mag in their base than most other coco nutes

Also, I didn't see you running canna zym - this helped in my experience with canna

Kweku- You running cannazym every watering? I try and use it every 3 or 4 waterings. I dont think it can sit in a res, and I make my res up for about 5 days worth of nutes.

I'm also thinking of getting Canna boost and PK 13/14. I'll for sure get the boost.

I think it would be good to start giving em A + B + boost, at least 3 or 4 waterings per week. Also unsure of how much pk13/14 to add.

So far, the plan is to flush 1g through each pot tonight, of .1EC calmag, .7 EC A + B, cannazyme and drip clean. Tomorrow, I will either flush once more, or give them .1EC calmag, A+B+boost (MAYBE PK13/14), at 1.6 EC.

I see pk get implemented much more frequently than boost. Search the forums here - mixed opinions on boost.

The pk seems to be effective based on hearsay - but I used other additives other than canna brand and ultimately stopped using it altogether. I didn't like the sweet chemmy smells, and prefer shitty stinky organics

I used cannazym every time. I believe it may cause pH to sway upward but not nearly like sm90, and sm90 only lasts about 24-36 hours before it starts pushing pH upward. Also, it's sterilizing qualities diminish significantly after the 24 hr mark (as per the phone rep at nutrilife or whoever makes that junk) I also quit using sm90 in favour of bacterial and fungal cultures in the rhizosphere. Organic and symbiotic coco definitely is better to my tastes than canna.

Let me recommend slf-100 by cascade organics. It's basically a cannazym + dripclean minus the fertilizers. Organic and 0-0-0

But cannazym worked well with canna coco ab. If I were to use any canna product again it would be cannazym

Looks like I'll foliar feed lightly with boost, and start giving em PK13/14 TOMORROW, after todays flush. I'm thinking I'll flush with .5 EC water, at least 1 gallon per plant. Will be interesting to test runoff.

I'll recheck my bottle of cannazyme, and start using it in my res if it allows.

Here's more pictures from last night.

Some more shots. Notice the curling/twisting of the small single leaf blades coming out of the buds. Also a shot of the underbelly of the canopy. Very few leaves on bottom show any distortion, but there is definitely small amount of some kind of deficiency/toxicity showing.

And lastly, here's some leaf shots. I scoped em last night, trying to see any broad mite eggs, and was unable to find them. Perhaps my scope isn't strong enough to be able to destinguish BM eggs, but I DID notice many unusual little spheres, almost like trich heads, On tops and bottoms of leaves with absolutely no crystal on them, as well as sugary leaves. Last picture is a stem of a leaf.

I dropped the cal-mag around day 28 on a 63 cut strain. However I did this in a room running lower temp and RH than you are, with no suppliment co2. I did 1gpw in 3gal smarts 3x plants under each 1000w.




If I were in your shoes, and since your plants are being hit with a nice vpd with high co2, I would bump the ec to 1.6-1.7, possibly drop cal mag or not, your leaves look like they are enjoying an abundance of nitrogen, however some chem cuts thrive on calmag, so idk.




I would add PK 13/14 around day 40 and go till 45 with your strains.

Canna Boost is amazing, especially if incoroporated early

I honestly feel guilty using cannazyme personally as I have not done any tests on it. However I will bounce between 5ml/gal every feed to every other feed, I havent had any negative results letting cannazyme sit for 3 days.

I also use Ful Power or recently I have switched to New Millenium Ruby as it is considerably cheaper and made locally, or Sea Crop.

Does your leaf yellowing happen mostly under the most intense lighting part of the canopy?

Actually, I would drop the calmag

Co2 issue? 1000 ppm co2. Isnt 800 the optimum?