See if this can help…good luck… I’ve grown auto’s also there’s a lot of don’t associated with em. But it’s myth. But i don’t know what’s ur issue… Ur water might have other contaminants. Try bottles spring water or rain water… Put a large bin outside an catch rain water… But check out link above im sure it will help
Theres also an AI app called GrowDoc… U take a picture and it diagnose it and gives u a solution
BEST OF LUCK GROWMIE.
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I hate using peat indoors as it takes to long to dry out and that usually turns to root rot or nutrient deficiencies . I rec Ditching the peat and use a mix of 50%coir / 50% perlite along with a quality brand of synthetic liquid nutrients . This mix can be watered from every day to every few days depending on the setup but should never be allowed to totally dry out . Sense this is now classified as hydroponics you should treat it the same. My coir set up is using dyna-gro nutrient line and following there scedule .My ph is usually back and forth between 5.8 and 6.3 for watering and I usually start at about 350ppm@5 at seedling/clone and gradually take it to about 1300ppm during flowering. There also should be alittle runoff every watering to flush out old nutrients so there isn’t a build up in the medium. I rarely have a problem using this method other than my plants looking to healthy and green at harvest but I guess I could flush more towards the end if I wanted yellow leaves
I’m starting to wonder if you have a pathogen in the mix. I don’t see any typical indication of spider mites, perhaps a toxic fungus attacking the meristem. Do you have an IPM practice? I was turned on to a product not long ago called Grow Safe that has really impressed me with spider mites and PM issues. There are tutorials on YouTube for making LABS with rice water which could be an option, alot of folks swear by it. Hydrogen peroxide has mixed results but could be a place to start as well.
Looks like iron deficiency
I use a calmag that has extra iron in it
If it is iron and you rectify it , plants will green back up quickly , 5-7 days and growth will resume
Your coco plants looks like p deficiency
Npk ratio x/?/x , on front or back of bottle nutes
? Lower than the rest
: )
When I use coco I put 3-4 tbs of GIA green 4/4/4 and 2/8/4 that’s 8 tbs all together per gallon of coco mixed in with a heapin helpin of worm castings
Ro/di water PHed to 5.7. With a cal/mag additive Watering every 3-4 days until run off
Didn’t really do a TDS reading
As soon as they have 2-3 nodes I spray several times a day with PHed water with a cal/ mag solution
30 days after up potting I’ll top dress with the 5 tbs of the 4/4/4 and worm castings
60 days later top dress with 5 tbs of the 2/8/4 and worm castings
No more nutes just PHed water with cal/mag added
Plus spraying several times a day
I keep temp in tent/room at around 85 w/ RH between 45-60
I will use both MH/HPS lighting or LEDs depending on my mood and how much my budget will allow
First pic is current grow using LEDs
Secon pic is previous grow using MH/HPS
Thats too much nutes. Tbh plants hardly even need nutrients except for nitrogen during veg if even that. You can make it pretty far on just proper ph and not having nutes locked out. It’s almost better for them to show signs of a deficiency before adding anything nute wise. Especially anything outside of nitrogen.
In veg , n is for leaf and stem , p is for roots and k is for plant health ( generally speaking )
They need all three , in an equal balanced feed 1/1/1 or similar
: )
Small update
As of today, no new growth has died so far. The top growth of the smaller plant seems to come out VERY slowly, maybe a bit too light of a green, but it’s something. Right now I’m only watering in minimal amounts, with almost no runoff, and very low EC.
The big plant doesn’t have and new symptoms so far, too. No more droopy stems, leaves are horizontal, not drooping, nothing. It does look like it smoked crack for 5 years, daily, but it seems alive and okay right now. Also some new growth here and there, but only tiny ones. But tiny is big in this case.
The auto in peat? Yeah, I already had iron in my mind back when my first two autos in peat died. It looks like an iron deficiency, I couldn’t find a good other example of a nutrient deficiency. I just don’t know why it ALWAYS happens in my organic peat, even after changing to a new batch of that stuff.
Here’s my first grow ever, with two autos, exactly the same symptoms. I kept them alive for almost 2 more months when this happened, and NOTHING has helped. Until they just died.
My 3 new seeds are already planted in their 1L seedling pots with a 40/60 perlite coco mix, and some root stim and myco. I’m excited, but also very scared about all this sh- coming back to haunt me again.
Is there a good guide for coco which isn’t cocoforcannabis? It’s the guide I mostly followed, and it went absolutely sideways.
Your iron deficiency is almost certainly caused by pH issues and not a lack of iron.
I still don’t know how pH can cause this, or rather how it can be pH issues if I always correct my pH. My pen is always calibrated, it’s a rather good one (Apera ph20), I always stir the pen in the solution as recommended, and wait a bit to see where the pH will stop changing. In the organic substrate, I always aim for 6.3-6.5, it should be fine or?
Do you have test drops? Test strips? I would question the accuracy of your meter. While the drops are not as precise they are never wrong. I keep them on hand as a double check for if things go sideways.
It’s not the pH of the input necessarily, It’s the pH of the grow media that can affect things drastically if it’s out of range. You said you were getting a runoff of 6.5pH when putting in a pH of 5.8 or something so I’m guessing your media pH is way too high atm. Could be caused by the plant taking up more anions than cations or just general buildup. It’s pretty good practice to feed to runoff every time you feed to try and “reset the media” but you also don’t want to be feeding everyday if the plants aren’t growing/ uptaking anything.
Using a fertilizer with a bit of it’s N being from ammonium can help drop the pH of the media much more effectively than lowering the pH of the input. Something like YaraLiva calcium nitrate
My media is around 5.5. My nutes are 7. Mix them together your on target. If I’m too lazy and let them dry out. Eliminating the water, I start to get problems.
Seriously though, get the drops. They are cheap but valuable.
Solve this problem by next time adding organic container mix soil to the coco and perlite. Then just use nutrients that are PH perfect. Don’t have to PH.
Are you using the cannazyme/rhizotonic? I’ve read on riu and other forums years ago of users ditching it and seeing good results.
Also regarding nutrients, just for the sake of simplicity, and since ur familiar with cocoforcannabis.com, why don’t you get yourself the gh flora series along with their calmag.
I use the instruction on the back of the bottle and feed at max 1.5ec or 700-750ppm.
Hope this helps. 
You mentioned using epsom salts but don’t state how much. --stop. It’s not necessary, and you might be overdoing it.
Aim for more of a pH of 6.3 to 6.5 *the newest info out there, per Dr. Bruce Bugbee, is that ALL media should aim for a pH of 6.5 at all times. Some movement is good, and, aiming for a higher pH such as 6.3 is beneficial in the event that you may get salt/nutrient buildup in coco which in turn lowers pH of the rootzone. …
Insect frass is a good addition I’ve read that ways with coco. Never tried it but sure does have nutrients that will break down overtime. Need to incorporate microbes or otherwise it’s not happening.
Below is an analysis of mealworm frass available locally:
I always supplement every feeding with microbe and kelp. That stuff looks good…
Insect frass is a staple for me, soldier fly particularly. In fact, this may help OP with his new sprouts.
I make sure my seedlings get some specific things at or near birth to turn on the immunity dip switches; frass, and Aspirin, kelp and alfalfa meal. Chitin found in the frass and acetylsalicylic acid in Aspirin both trigger mechanisms in the plants immune system that handle insect and microbial activity. Triacontanol is a growth regulator found in alfalfa that not only boosts growth but also aids in heat resistance. There’s also a load of micro nutes and beneficials in it. Same with kelp meal. I have found it critical to get these to the plant near birth to get the switches on for its entire life. This practice makes plants that are ready to fight back and growth is noticeably more robust.
It’s hard to find insect frass where I live, it seems like I can only import it, with rather expensive shipping. I also don’t know if this works with a pure coco grow with chemical nutrients? I’m a beginner, so I can just ask.
My seedlings are currently sprouting, I think they’ll pop out tomorrow. I just hope it’ll work this time. The two coco plants didn’t change, but they also didn’t get worse currently. The auto has dying leaves on the bottom which look like P deficiency, slowly spreading.
I’m still fascinated about the fact that I grew one plant just for fun around 9 years ago. Random bag seed, random basement soil, and tomato nutrients. It yielded 8oz without acting up once. I didn’t know about PH, EC, chlorine, anything. Just a 300W HPS, a cheap clip-on fan, a cupboard I painted white, an old bucket with some holes, and… huge plant. I’m talking huuuuge plant. Those big main colas were arm-sized. I thought that’s how easy it is.
I wish I could invest more in special stuff, but I’m already at zero & just trying to get the best out of what I have, as I do this for my sister who’s in a severe psychosis. Refuses to go into therapy (too old, she has to decide for herself), and the only thing that helps her is weed, so she stops talking to herself / smashing objects into walls. Weed is insanely expensive where I live, especially if you want to buy it legally. Like really expensive. So all that’s left for me is growing it, but this stuff is getting really expensive now too as I’ve so far killed all of my plants early on with the same symptoms in different substrates / with different nutrients.
This ain’t as easy as I thought 
