Twisted stunted growth rdwc problem

fuffybud · Apr 21, 2026

Hi all new to the page.
Im currently growing in alien rdwc 100L 6 plants. Not sure on plant limits so please correct me.
Plants are nearly 3 weeks old but 3 are stunted with no new growth.
Im using canna aqua A and B with calmag as I have a soft water.
So I've started of with 50mil a and b and 50mil calmag
My ph is 6.1
My ppm 630 it was stronger but I diluted it down since the problem started showing.
Just wondering if anyone has had similar issues in rdwc system
Thanks

JIMKSI64 · Apr 21, 2026

pH control.
How do you do it?
630 can be way hot depending on water source ppm.
Give us your data on water ppm and then nutrient mix ppm
My first impression is that plant is done as the new growth nodes look fried and the backups normally do not show till node 3.

fuffybud · Apr 21, 2026

JIMKSI64 said:
pH control.
How do you do it?

Use ph down or up in the main rez with syringe depending what the ph is. I've just had to give 1 mil of down to bring the ph to 5.6 at the minute.

fuffybud · Apr 21, 2026

This is the stats of the water.

JIMKSI64 · Apr 21, 2026

What was the ppm and pH the last time the plant looked good? Did you make a large nutrition change?

JIMKSI64 · Apr 21, 2026

Ok hey big question.
It looks like that is an automated sensor system. Do you have any way to verify both ppm and pH with another backup tool?
Is there a calibration test procedure for the system?

Grownsince95 · Apr 21, 2026

Looks like broad/russet mite damage. I'd bet money on it. You need a microscope to see them and nuclear weapons to get rid of them.

Sorry to say but that plant is likely toast and you have a bit of a cleaning project to do now.

fuffybud · Apr 21, 2026

JIMKSI64 said:
Ok hey big question.
It looks like that is an automated sensor system. Do you have any way to verify both ppm and pH with another backup tool?
Is there a calibration test procedure for the system?

So when I first put them in the system they looked all healthy and maybe a week after I noticed 3 of the 6 in started with the yellowing first followed by the abnormal leafs.
The feed chart said to give them 139mil per 100L but I give them 60mil AB and the ppm was 800 or so but since I've lowered it down to 50mil per 100l. I've used essentials ph pen with a ac infinity ph/ec pen both calibrated the readings in the image is with the new ac infinity hydro sensors and that's also been calibrated. And now I've just ordered another ph/ec pen to check with the others lol. I know in hydroponics with soft water you are supposed to use calmag because the waters to soft and lacks these but I run out so that's on order.
I did have something like this before but I did manage to sort it but unsure what the problem was ph,ec,light,air,water temperature but it set me back loads.

fuffybud · Apr 21, 2026

Grownsince95 said:
Looks like broad/russet mite damage. I'd bet money on it. You need a microscope to see them and nuclear weapons to get rid of them.

Sorry to say but that plant is likely toast and you have a bit of a cleaning project to do now.

Hi no its definitely not insects I've had the scope out and can't see nothing at all. That's the first thing I looked for.

Grownsince95 · Apr 21, 2026

fuffybud said:
Hi no its definitely not insects I've had the scope out and can't see nothing at all. That's the first thing I looked for.

What kind of scope?

fuffybud · Apr 21, 2026

Grownsince95 said:
What kind of scope?

One of the loop ones bit similar to a jewelry one

JIMKSI64 · Apr 21, 2026

My opinion is that with calibration being in the zone and the numbers at 800 are nuts that young but only 3 of 6 plants " have it".
Def get a 30x60x scope on the leaves top and bottom and look for bugs like G95 said.

Grownsince95 · Apr 21, 2026

fuffybud said:
One of the loop ones bit similar to a jewelry one

Nope. I said microscope. You need at least 100x power to see them

Grownsince95 · Apr 21, 2026

If you want to save your other plants the infected ones need to go now. And that might still be too late.

Ask me how I know... lol

Good luck and keep us posted!!!

Grownsince95 · Apr 21, 2026

JIMKSI64 said:
My opinion is that with calibration being in the zone and the numbers at 800 are nuts that young but only 3 of 6 plants " have it".
Def get a 30x60x scope on the leaves top and bottom and look for bugs like G95 said.

Bingo. Now that's how you diagnose cannabis problems!!

fuffybud · Apr 21, 2026

JIMKSI64 said:
My opinion is that with calibration being in the zone and the numbers at 800 are nuts that young but only 3 of 6 plants " have it".
Def get a 30x60x scope on the leaves top and bottom and look for bugs like G95 said.

I thought same with numbers I've brought the ppm down now to 550 or so but still maybe strong and 3 having it on the same linked system is strange ill have a look now

Grownsince95 · Apr 21, 2026

30x is not enough. 60x minimum and they will still be difficult to see. They hide in the microscopic folds in the leaves. At 60x you might catch a little "movement" if you look long enough, plus it takes patience because at that magnification you are only covering a very small section of the leaf at a time.

I've been growing for 30 years and got my first broad mite infection last year. I thought my light was too strong. By the time I figured it out I lost the whole tent three weeks into flower.

fuffybud · Apr 21, 2026

Grownsince95 said:
30x is not enough. 60x minimum and they will still be difficult to see. They hide in the microscopic folds in the leaves. At 60x you might catch a little "movement" if you look long enough, plus it takes patience because at that magnification you are only covering a very small section of the leaf at a time.

I've been growing for 30 years and got my first broad mite infection last year. I thought my light was too strong. By the time I figured it out I lost the whole tent three weeks into flower.

No way. Ill definitely have a look

JIMKSI64 · Apr 21, 2026

fuffybud said:
I thought same with numbers I've brought the ppm down now to 550 or so but still maybe strong and 3 having it on the same linked system is strange ill have a look now

I am going to narrow my answer / guess.
The 800 focused on nutrition. The deep green focused on nutrition. But I have had a few nitrogen issues and had a nitrogen burn on my hydro and it went deep green yellow dead in like 40 hours.
One of the signatures of deep green burn is tip curl and the leafs become puffy. This is a perfect insect vector. Puffy soft leafs.
Can be more than one thing wrong and one thing can make other things happen.

Grownsince95 · Apr 21, 2026

JIMKSI64 said:
I am going to narrow my answer / guess.
The 800 focused on nutrition. The deep green focused on nutrition. But I have had a few nitrogen issues and had a nitrogen burn on my hydro and it went deep green yellow dead in like 40 hours.
One of the signatures of deep green burn is tip curl and the leafs become puffy. This is a perfect insect vector. Puffy soft leafs.
Can be more than one thing wrong and one thing can make other things happen.

Some growers play checkers, you my friend are playing 4D chess

Twisted stunted growth rdwc problem

Twisted stunted growth rdwc problem

fuffybud

Attachments

JIMKSI64

fuffybud

fuffybud

Attachments

JIMKSI64

JIMKSI64

Grownsince95

🤘😆👍

fuffybud

fuffybud

Grownsince95

🤘😆👍

fuffybud

JIMKSI64

Grownsince95

🤘😆👍

Grownsince95

🤘😆👍

Grownsince95

🤘😆👍

fuffybud

Grownsince95

🤘😆👍

fuffybud

JIMKSI64

Grownsince95

🤘😆👍

Twisted stunted growth rdwc problem

Twisted stunted growth rdwc problem

fuffybud

Attachments

JIMKSI64

fuffybud

fuffybud

Attachments

JIMKSI64

JIMKSI64

Grownsince95

🤘😆👍

fuffybud

fuffybud

Grownsince95

🤘😆👍

fuffybud

JIMKSI64

Grownsince95

🤘😆👍

Grownsince95

🤘😆👍

Grownsince95

🤘😆👍

fuffybud

Grownsince95

🤘😆👍

fuffybud

JIMKSI64

Grownsince95

🤘😆👍

Privacy & Transparency

Privacy & Transparency