My plants are dying and no one knows why. I need help!

[bili_isiro]

Hi guys,

I'm new here and desperately looking for help. I've done a lot of research and talked to several people, but I haven't found a solution yet.
I'm having the same problem with my mother plants and the clones I took from them.

My mother plants are almost 4 months old. Strain: Glue #31 compound genetics.
30 days ago, they started to show burns on the tips of the upper leaves. These burns spread throughout the leaf until they kill the entire leaf.
The new leaves grow smaller and smaller until the problem takes over the entire plant and it dies (I've already lost 5 plants in the same way).

I uploaded some photos and a video so you can better assess the situation.
Does anyone have any idea what's attacking my plants?

Watering and Grow Room Information
Sealed room
Coconut fiber soil
2 gallon pots
Strain: Glue #31 Compound Genetics
Input EC 1.4 / Output EC 1.8-2.2
Input pH 6.0 / Output pH 5.9-6.5
Runoff 30-40%
Watering once a day (0.5L to 1L depending on the plant)
PPFD 350-450
CO2 500-800ppm
Room temperature 25-27°C / 77-80°F
Room humidity 60-70%
Watering solution: plantprod calmag 13-0-13 (1g/L), ppmj grow (1g/L), silicate (0.4g/L), seacrop (1mL/L) and H2O2-hydrogen peroxide (1mL/L)

Tkx a lot!

 

[ChaseH]

That looks bad. What do the roots look like?

 

[BB22]

The healthy, green growth…then crispy. That sucks OP. Thanks for sharing . Interested in how this plays out

 

[GNick55]

i think @Choppr knows about griwing in coco,.
he should be by with this tag,.

 

[Phyto]

Not a big coco guy, but what jumps out at me in is the ec in and ec out. There may be a salt build-up issue in the coco. Hopefully it was pre-washed and buffered. But I think I would start with a zero nute flush until you get the ec down, followed immediately by a normal feeding. I have no clue as to how CO2 may play into that. But again, I’m not a huge coco guy, so hopefully others will chime in.

 

[HerbalEdu]

not a coco specialist either but this is what google says:

High EC in run off could mean that salts are building up in the root zone and you may need to water more frequently with lower volume and same dosage of nutes, but relative to the volume of water you're using. Run off ec should be no more than 300 higher than solution ec.

How to Manage Run-off EC - Coco For Cannabis

Learn how to manage Elelctrical Conductivity (EC) in your coco grow. Simple instructions how to control EC to maximize growth & keep plants happy & healthy!

www.cocoforcannabis.com

 

[HerbalEdu]

from the previous article in the link:

If Run-off EC is:(Compared to inflow)	Status	Action
Lower than inflow EC	Anomaly	Not a problem. Should self-correct.
Within +200*	Ideal	Monitor EC twice weekly
+200 to +300	Acceptable	Monitor EC daily, consider increasing fertigation frequency
+300 to +400	Caution	Increase fertigation frequency and/or Increase quantity of run-off.
+400 or Higher	Danger	Consider flushing: See “When and How to Flush Cannabis Plants”

*EC values expressed in Microsiemens. 200 microsiemens = 0.2 millisiemens

your run off ec is 400 to 800 higher than it should.

 

[bili_isiro]

That looks bad. What do the roots look like?

Apparently the roots are weak, this week I took a picture (see below) of the roots of one of the plants that died, I also cut the stem in half.

 

[bili_isiro]

Hopefully it was pre-washed and buffered.

Yes, it was!

But I think I would start with a zero nute flush until you get the ec down, followed immediately by a normal feeding.

Thanks man, today I watered with the same solution (1.4EC/6.0pH), but with a large volume (3L for each plant).
The runoff varied between EC 1.6-1.8 and pH 6.0-6.5 depending on the plant.
So I think I should do what you have recommended.

 

[Oldchucky]

Looks like plenty of roots to support that plant if the roots were doing their job!

 

[bili_isiro]

from the previous article in the link:

If Run-off EC is:(Compared to inflow)	Status	Action
Lower than inflow EC	Anomaly	Not a problem. Should self-correct.
Within +200*	Ideal	Monitor EC twice weekly
+200 to +300	Acceptable	Monitor EC daily, consider increasing fertigation frequency
+300 to +400	Caution	Increase fertigation frequency and/or Increase quantity of run-off.
+400 or Higher	Danger	Consider flushing: See “When and How to Flush Cannabis Plants”

*EC values expressed in Microsiemens. 200 microsiemens = 0.2 millisiemens

your run off ec is 400 to 800 higher than it should.

Thanks for that, man.
My runoff ec was in the danger zone, so I need to take some actions about this.
Today I watered with the same solution (1.4EC/6.0pH), but with a large volume (3L for each plant), runoff varied between EC 1.6-1.8 and pH 6.0-6.5 depending on the plant. Its already out of danger zone but I need to have caution and take quickly actions like increase watering frequency as you said. Thanks!

 

[Grownsince95]

What is your water source? Well, municipal or RO? What are the ppm and EC of the source of it's not Ro?

You're using a 14-0-14 cal/mag which I don't really recommend and could be causing your problems depending on your water source and how you use.

Fear not my friend will will get to the bottom of this.

Also need to know what kind of light you're using

 

[bili_isiro]

Looks like plenty of roots to support that plant if the roots were doing their job!

Good to know that, so the problem should be something different.
Do you think it could be some fungus? Like fusarium?

 

[Gmix]

As the camera was bouncing around in the video I caught this

Looks like fungi

 

[bili_isiro]

What is your water source? Well, municipal or RO? What are the ppm and EC of the source of it's not Ro?

Well water, EC 0.15 and pH 8.2.

You're using a 14-0-14 cal/mag which I don't really recommend and could be causing your problems depending on your water source and how you use.

Thanks for that, man. What do you recommend?

Fear not my friend will will get to the bottom of this.

Best advice I ever received. Very grateful for that, really.

Also need to know what kind of light you're using

2x Vivosun AeroLight Wing AW200SE Full Spectrum LED Grow Light 200W for the mother plants.

 

[LoveGrowingIt]

Looks like fungi

WPM, perhaps?

 

[Oldchucky]

Good to know that, so the problem should be something different.
Do you think it could be some fungus? Like fusarium?

I think if it was fusarium, he would see a lot more damage on the stalk and branches! I think they look pretty healthy. Other than being may be a little anorexic! And pythium would probably eat your root ball down to a little frazzle. Don’t see anything real abnormal about it either! Looks like my root balls when I rip my plants up! Looks like it just doesn’t like what you’re trying to cram down its throat! And there may be A few spots of W p.m. on the leaves! Hard to tell! Just two cents! As a Hail Mary, you could probably transplant them into some ocean forest and possibly Save them! But listen to these other folks! I usually don’t know what I’m talking about!

 

[bili_isiro]

As the camera was bouncing around in the video I caught this

Looks like fungi

Thanks man, these white spots are actually remnants of a foliar watering that I had done a few days before making this video.

 

[Grownsince95]

Your well is naturally alkaline because of the Calcium and magnesium already in there. You should ditch the cal mag in my opinion.

If not, cut your dose by at least 75%

 

[Grownsince95]

I just read up on the nutes your using because I wasn't that familiar and I think you're also double dosing you micronutrients like iron, Mb etc...

Both your calmag and grow formula contain a full suite of micros. I'm not sure how compatible they are together in a coco coir substrate.