Impossible to find cause - Why are my leaves blotchy yellow and dying on top?

[Shneex0338]

Hey guys, quick info:

• Autopots, 3.9gal, 4 pots + Reservoir. All plants feeding from the same reservoir.
• Canna coco nutrients, coco perlite 60/40 mix, synthetic
• RO / Tapwater, mixed 75/25 for stability
• EC 2.4 currently, but also tried 1.4 for 2+ weeks
• PPFD around 800, 20/4 cycle, autoflowers, day 60 mid flower
• PH 5.5-5.6 in the reservoir, PH in the trays around 5.8-5.9

As of ~20 days ago, weird yellow tips grew out on one of the plants. And now it's pure chaos. Leaves dying everywhere on the top canopy, really weird blotchy yellow leaves, very sharp contrasts, some nute burn here and there probably. GWE doctor is absolutely not able to help, it's impossible to find the cause of whatever this is. I tried really low EC, I even flushed this plant (over 120L of 0.8EC solution + surfactant through one pot), and and and. It keeps spreading.

I am clueless, hopeless, nothing has helped. This plant also seems to be stuck in mid flower the leaves all feel "soft to the touch", rather than having stability. This plant is not underwatered or overwatered, the leaves are praying, the autopot trays are working as intended, everything seems to be.. fine for some reason.

This plant is the worst, another plant is yellowing on top too, but in a more passive slow way, which is still worrying, but a bit different. The other 2 plants are totally fine for some reason, nothing seems to be wrong.



The other yellowing plant:



What the hell is going on here? Can this be root rot? I had to remove the root copper disk from these pots by removing the pot so I can flush them, luckily damaged nothing, but I noticed a "fart" smell coming from one of them. Roots looked healthy, but that smell was a bit suspicious.

[Bluey]

An EC of 2.4 will cause yellow tips. Drop it back to 1.8 and see how that goes. 1.6 to 2.0 is usually max but depends on lighting and environment. Try pH 5.8 or slightly higher in the reservoir.

Fart smell can mean root rot and you can also get it from a mix of incompatible nutes. You need to use a root conditioner or some such chemical to treat the water if using a reservoir and hydro. I don't know much about that so best someone who grows that way pipes in here.

RO water is preferable to a mix of tap and RO.

The leaf symptoms may be an issue with your pH and I think it is effecting or locking out the nutes it wants most in flower, P & K.

I don't thinknit is temp or himidity related but reduce your lights until you get it sorted.

[Gingerbeard]

Late-stage flowering. There. I said it. Why am I the one who every suggests late-stage flowering? Because it is not covered on GWE? Maaannn...
I don't know about all those corrections, but plants can do what this plant is doing when it is getting ready to be harvested. Correct everything all pretty but your plants are fine. If all the plants are being fed the same thing in the same medium for the same amount of time and one plant is issued, that one plant has a problem or that one plant is showing its phenotypical self. If those leaves were turning purple, which is also a nutrient thing, not a damn one of you people would suggest correction. Green: good. Purple: pretty. Yellow: yucky.
Let us close our eyes for a moment and imagine so I don't have to take a picture and upload it and junk.
I have two plants in the same pot. Seeds came from the same plant. Planted at the same time. Obviously, each gets exactly what the other gets. As do the 4 plants in the other 3 pots. One plant looks like it's going to be harvested pretty quick. Mostly amber hairs and beat-up, pale leaves. The other plant looks like it has some time. The only difference is phenotype.
If the roots are not farting and the res is good, what about what the pots are sitting in? I don't get much runoff from my bags, but I still get goo in the saucers under them.
Wsshhhheeewww-E it feels good to get that out! I need a dab.

[golfnrl]

I grow in autopots. Those pics look like PH problems to me. And perhaps nutrient and light burn. I've never flushed a plant and pulled the copper lined pot sock while the plant was growing. Those things are supposed to help keep the roots out of the water. I can only get one or two uses out of them and then they lose their effectiveness. That could contribute to the fart smell. In the past I have syphoned out the pot reservoirs to correct a PH problem, caused by a gardening while stoned moment. Not saying that you shouldn't read the trichomes about harvest readiness as others have suggested.

I have the exact same setup. The PH controller keeps my rez maintained at 5.9 to 6.1. I never check the PH in the pots. I grow using 50/50 coco/perlite. I use CX Horticulture nutes, their full line. You do need some kind rez conditioner for hydro. The CX ReGeneroot and WiltGard work really well. Do you have a pump in the rez? If not, consider a small aquarium pump set to run 5-10 mins 4-6 times a day. That and the rez conditioner will help keep the water stable. What kind of light are you using? How high above the canopy?

[Allenpro]

When I grow in coco coir I keep the PH 5.9-6.2, I dont care about the PH in runoff nor do I care about wet weight, but thats a different subject.

[dirtymike]

Harvest is coming, ride it out.

[Franklin]

Looks like some pics I've seen of mosaic virus

[dirtymike]

Mosaic is more defined from my experience. It looks like the flowers are taking over and demanding everything it needs. I would test the water for correct PH and adjust. Flowering stage is new ball game. Do one thing at a time and wait for results.

[Shneex0338]

A little update:

First of all - Not late stage flowering. This plant has around 30-40 days left. It's not even bulking yet, it's still growing pistils and is very thin. I'd expect "late stage flowering" if I flush (which I won't, because that's goofy) and deprive my plants of any nutrients, so they "fade" or whatever people call it (They're dying of hunger). I know what late stage flowering is, and it usually doesn't deep-fry my plants.

As of 2 days ago I am using Athena Cleanse in my res, some stuff to absolutely obliterate any organic matter & also to keep the lines and everything clean, and the difference in res smell is already worlds different. No more stinky aquarium smell, the res water looks 100% clean and clear, it's noticeable, night and day difference. As of this time, no more damage is spreading for now. My smallest yellow plant is apparently getting some color back too. The big actual problematic plant is still visibly damaged, but it's turning really frosty now, but still no bulk as of yet. I imagine it won't be a full harvest with all plants at the same time, as this one will take its time.

I don't know what fixed it - Lowering EC from 2.4 to 2EC, using Athena Cleanse now & staying away from ANY organic boosters from Canna (even if they're hydro friendly, f that), keeping my res PH below 5.8, or moving the light a bit further up (around 800PPFD at 20/4 now). I have no idea.

But as I said - no more damage spreading for now.

Here is a general look into my 5x5 / 150x150 tent with 4 Autoflowers in it if anyone is interested:

2x Granite Haze F5 Speedrunseeds
2x Acid Snow Speedrunseeds



Generally, everything is fine so far. The left bottom plant had a "light" version of this damage, it just generally started yellowing on top. The "bad one" is the one in the top right, but she's good for now too.

The other two plants (front right, back left) are 100% healthy, a little burn here and there, but that's it.

No idea what fixed it, but it was one of the things listed above. Thanks for the help!

[Bluey]

Hey

I posted a solution to this under the cloning aeroponics bucket thread.

You cut black (don't use white, they failed me, but I also think they were a low to medium density) foam. I can't remember the name of it but I also posted a link to Walmart on the type of foam. It's waterproof too. Easy to work with too. Lights are often packaged in it for shipping. It's the stuff you find in Pelican cases.

[golfnrl]

Bluey. I couldn't find the thread but I do know the foam you're talking about. Hadn't considered that.

[Bluey]

golfnrl https://forum.growweedeasy.com/forum...408#post618408

[Radeon]

Harvest is coming, ride it out.

Bingo! Let them go. It's WAY too late in the game. They don't have much longer. Gonna be some good smoke...congrats!

[golfnrl]

So how did it go? Do you have harvest pics?