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Slow root growth in RDWC

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Slow root growth in RDWC

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kiwibud

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Hey guys, hope anyone can help me out as I'm in desperate need of help with my RDWC.
Done about any System available with success, however I started with RDWC last year due to plant count in my country to stay legal.

Anyways, problem is this super slow growth of roots once they are in the water in their totes.
Tried anything, read about every thread on the Internet about RDWC and I usually really dont post on forums so you are kinda my last hope before I trash this whole setup (which I put a shitload of money into).

4 plants in 5 x 10 tent (Lumpys AF currently)
-tried Super Buff Cherry and Dantes Inferno 8 before
SBC worked best

2000 watts of LM301B LEDs
4 x 60 liter Totes and another 60L Res in which I mix the nutrients and have a Cooler running

Temps ~23 to 28 Celsius
Water temp constant 19°
Ph 5,6 to 6
Ppm ~500 to 600, with tap water
Using Epsom salt, TA maxibloom, Great White shark (tried sterile before)

clones are rooted in diy aero cloner, transplanted with ~30 to 40cm long roots, hit water level reasonably quick (could be better tho)

But once they are in the water, it takes AGES, some times they dont grow any more roots for 2 weeks, sometimes they seem stunted and at some point they take off like crazy which is usually when they are *months* in their totes.

The very first run with the SBC however they took off after just 2 weeks or so.
The 2 Dantes didnt take it half as well tho.

System is cleaned with bleach inbetween runs, thorougly rinsed and fine afterwads.

If you have any suggestions, tips or find the problem, let me know. I'm out of ideas.

2 huge bushes in the back, been in there since March 23nd (not on pics)

These 2 plants are in there since 1st of june and look like 2 weeks old.

I really dont think it should take me 4 1/2 months for them to reach a point I can put them into flower.
Somethings fishy here.

Many thanks in advance.
 

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roots look good.
but Ppm ~500 to 600, with tap water could be low since some tap waters are 400 ppms no idea what yours is but easy way to see if you have enough nutes is if in 1-2 days the ppms drops or raises then you know if she is eating or starving...
and from the look of your long and thin plants i would also say your not pushing the light hard enough or maybe its just because you dont train your plants i havent seen untrained plants in a long time...
 
Also using tap water there will be chlorine in trace amounts but enough to kill or throw off your benis

Your benis will be responsible for your enzymes nd fungi to promote root growth

Could be wrong but just my first thought
 
roots look good.
but Ppm ~500 to 600, with tap water could be low since some tap waters are 400 ppms no idea what yours is but easy way to see if you have enough nutes is if in 1-2 days the ppms drops or raises then you know if she is eating or starving...
and from the look of your long and thin plants i would also say your not pushing the light hard enough or maybe its just because you dont train your plants i havent seen untrained plants in a long time...
Hey, thanks for the suggestions.
Since the whole system is around 300 liters/ 80 gallons the ppm dont really move at all with 4 plants in it.
Drop by 10ppm max in 2 weeks.
Tap water is 287ppm no chlorine.
Ph 7.6

I know this plant looks kinda atrocious, will take a pic of the whole tent later once the lights go on again
The 2 in the front both look this spindly, the other 2 in rdwc and the ones in autopots are scrogged and supercropped (waited way too long for the newer ones to pick up) and since its day 10 flower they are stretching into the lights - yea know this parts on me.

Is there any way to test, if they get enough oxygen?
Back when I was running e&f with no medium my roots would explode in a day or two as soon as they got in the tables.

So might be a lack of oxygen but anywhere I read, everyone says fallponics is superior.
 
Unless these are clones of plants you've grown before their genetics could be responsible for what your seeing. Also like Amnesia said, if your tap water is already almost 300 ppm they should be getting 900-1000 by the time your done adding food, especially with that much light.
 
Unless these are clones of plants you've grown before their genetics could be responsible for what your seeing. Also like Amnesia said, if your tap water is already almost 300 ppm they should be getting 900-1000 by the time your done adding food, especially with that much light.
I've grown the same AF before in coco - 0 problems there.
Some AF are in autopots in the same tent at around 1400ppm doing great.
Might be that they are just not made for rdwc. Will try with the same sbc next time for sure.

Also when I first started rdwc all plants burned with more than 750ppm and plants dont show any signs of being hungry right now, so dont think its about the ppm honestly.

Could the genetics really matter this much in rdwc?
Never had any problems in coco, ebbnflow, soil, nft no matter the strain.
Right now however it seems that they just go into shock for weeks until they eventually take off months later, albeit slowly.

As said above, will take some more pics once lights go on in about 2 1/2 hours.
Thanks for all the help so far guys!
 
Canopy aint even due to different age of the plants and me being a lil lazy.
One can tell they are doing okay, no signs of too much stress, not hungry, not burnt.

The two in the back in rdwc are  trees.
front 2 almost 2 months in the system and look like a wet noodle.

Anyone having an idea besides ppm?
So far wrong strain for the system seems the most plausible, other grow reports look way better with faster root growth tho.
 

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Hey, thanks for the suggestions.
Since the whole system is around 300 liters/ 80 gallons the ppm dont really move at all with 4 plants in it.
Drop by 10ppm max in 2 weeks.
Tap water is 287ppm no chlorine.
Ph 7.6

I know this plant looks kinda atrocious, will take a pic of the whole tent later once the lights go on again
The 2 in the front both look this spindly, the other 2 in rdwc and the ones in autopots are scrogged and supercropped (waited way too long for the newer ones to pick up) and since its day 10 flower they are stretching into the lights - yea know this parts on me.

Is there any way to test, if they get enough oxygen?
Back when I was running e&f with no medium my roots would explode in a day or two as soon as they got in the tables.

So might be a lack of oxygen but anywhere I read, everyone says fallponics is superior.
well i have 1 plant in 70L and it moves every day 10ppms or soo(even more when i give it too much or too little), after 2 days you should know
but your ph is horrible i hope the pen is broken because plants dont look that bad cosidering how high the ph is....
you can buy some cheap powder ph + or - few grams will fix you right up.

yea strech is a pain in the ass hope you made enough room soo you can work with the ones in the back without much backpains
as for how to test it i dont know i think you can buy an instrument.best i can tell you if they look droppy like they didnt drink water

and yea some strains really dont love hydroponics.from my experience some are sensitive to too much calcium from tap water.but the biggest problem i noticed is some strains are weak eaters even from the same seed pack.if one eats 500 and other eats 900 you will have a huge difference in plants.
my best plant i had was a 1500 eater and it was a monster compared to all others i had.
 
Canopy aint even due to different age of the plants and me being a lil lazy.
One can tell they are doing okay, no signs of too much stress, not hungry, not burnt.

The two in the back in rdwc are  trees.
front 2 almost 2 months in the system and look like a wet noodle.

Anyone having an idea besides ppm?
So far wrong strain for the system seems the most plausible, other grow reports look way better with faster root growth tho.

I have used liquid orca but not the dry that you have linked for bennys.

It's a good product but I find Hygroben from Hygrozyme to be far superior, price being number one and then two it’s way stronger if choosing this route.

Waterfalls do a good job at disrupting the surface to get oxygen in there and yes it’s all that’s needed.
Over the years of watching , reading I have picked up a couple things and added those to my own system to pertaps help in adding more oxygen.
Instead of a singie fall in each tote I have used 1/4 inch spray tubes , which may hit my net pots and agitate . This is also plumbed to my drain to pump out my totes when I want to change my nutes with a couple shut off valves to route.

I have found all strains grow just fine and that it’s only a 100 or 2 difference in ec .
1.2-1.4 ec is what works for me.

Personally I would be using that number on top of your the tap.
We don’t know exactly what’s in the 300.
I might put 150 ppm of calmag in my water first then add fertilizer to 1.5ec .
Plants are bigger and monitoring should be easy.
12 hr later were is ec? Adjust accordingly
Ec goes up and ph up then it’s too high.
Ec goes down ph up and it’s too low.
monitor until I found stability in both ec and ph.
5.8 for vegging and 6.0 for flower.

For myself only on complete charges would I ever experience swings in my ph for couple days .
I just keep adjusting as I know my Ec number is right and then couple days like a light switch it’s stopped.

Now the bennys .
It’s your choice how to add them , if I was just planting my plants , I would plant into my net pots .
Then I would determine how much liquid orca or Hygroben I’m using .
Split it into 4 , take a Dixie cup and dip into my tote water. Add the 1:4 into my cup .
Supercharged Benny Dixie cup. Pour that through 1 netpot into system.
Now do that 3 more times.
Bennys added.

Water level about an inch under roots and touching my net pots.

I would maybe every couple days , dip my Dixie cup and pour through the net pots making sure I don’t get bad stuff happening above the water line.

Once the roots hit water once a week would be enough .
 
I suggest you lower your ph to between 5.8 and 6.0 and test a liquid ph test kit vs what you are using now side by side comparison to see if they are even close to the same ph results. Also, your tap water has a very high ppm of 400ppm. You are on the cusp of having to go the R.O. route. Starting at 400ppm limits the amount of nutrient you can add by 400ppm. At this stage of veg you should be running around 650ppm nutrient . When you add your 400ppm tap that puts you in the 1050 ppm RANGE. You stated they can't take high ppm but get the environment dialed in and they will be able to handle the higher ppm much better. They look good but they are underfed. Also, waterfall ponics can be supplemented with Air Stones to enhance the oxygen levels in the nutrient reservoirs. I use one large air stone in my 130 qt igloo reservoir and 2 airstones per bucket. I also chill my water nutrient to 68 degrees to ensure oxygen levels are high and root rot is low... Im running dirty with hydroguard to eliminate root rot. So, add air stones to your reservoirs, cool your nutrient with chiller to 68 degrees, lower your ph levels to 5.8 - 6.0 range. Keep relative humidity about 60 percent. Up your nutrient levels (400 ppm tap water + 500 nutrient ppm = 900ppm) then monitor your ppm to see if its dropping every day. If its moving down then the plants are drinking. These are the changes I would make and monitor for change. Good luck with your grow, its totally salvageable so don't tear it all down. The PH is your biggest issue at the moment.
 
I have used liquid orca but not the dry that you have linked for bennys.

It's a good product but I find Hygroben from Hygrozyme to be far superior, price being number one and then two it’s way stronger if choosing this route.

Waterfalls do a good job at disrupting the surface to get oxygen in there and yes it’s all that’s needed.
Over the years of watching , reading I have picked up a couple things and added those to my own system to pertaps help in adding more oxygen.
Instead of a singie fall in each tote I have used 1/4 inch spray tubes , which may hit my net pots and agitate . This is also plumbed to my drain to pump out my totes when I want to change my nutes with a couple shut off valves to route.

I have found all strains grow just fine and that it’s only a 100 or 2 difference in ec .
1.2-1.4 ec is what works for me.

Personally I would be using that number on top of your the tap.
We don’t know exactly what’s in the 300.
I might put 150 ppm of calmag in my water first then add fertilizer to 1.5ec .
Plants are bigger and monitoring should be easy.
12 hr later were is ec? Adjust accordingly
Ec goes up and ph up then it’s too high.
Ec goes down ph up and it’s too low.
monitor until I found stability in both ec and ph.
5.8 for vegging and 6.0 for flower.

For myself only on complete charges would I ever experience swings in my ph for couple days .
I just keep adjusting as I know my Ec number is right and then couple days like a light switch it’s stopped.

Now the bennys .
It’s your choice how to add them , if I was just planting my plants , I would plant into my net pots .
Then I would determine how much liquid orca or Hygroben I’m using .
Split it into 4 , take a Dixie cup and dip into my tote water. Add the 1:4 into my cup .
Supercharged Benny Dixie cup. Pour that through 1 netpot into system.
Now do that 3 more times.
Bennys added.

Water level about an inch under roots and touching my net pots.

I would maybe every couple days , dip my Dixie cup and pour through the net pots making sure I don’t get bad stuff happening above the water line.

Once the roots hit water once a week would be enough .
Thats a very detailed response, thanks mate!
I'm reading into your product rn, gonna order that asap and try it out.
Maybe alternate with the GWS.

Was thinking about adjusting my falls, so far its 2 falls in each tote, might add another hose and put some more holes for outlets in.

My tap is already quite high in calcium, so figured out that adding epsom salt instead of calmag works better and I could see the changes, positive ones, in a day.

To all others mocking my ph - 7.6 ph is the water out of the tap.

Ph in res and totes is usually between 5.7 to 6.
As per your instructions I will up ppm a little to about 850 - 900ppm and monitor closely, same for any swings as others said too.
Would have had to up by now anyways since they are in flower but will do so on next run aswell.

Last 2 times I waited for the clones to come out of the aero cloner with long roots 30cm/ 12 inch, so roots were already through the net pot and in the water as I thought that would help with them taking off faster, they still went in kind of a shock and didnt grow for the next 1 1/2 weeks.

Anyway, will start with monitoring ph and ppm closely and try to keep it at 900ppm 6ph as close as possible.

Thanks for your help!
 
I don't know anything about EC or PPM I usually just keep my pH between 5.8 and 6.8and only adjust when it gets outside either end
 
I suggest you lower your ph to between 5.8 and 6.0 and test a liquid ph test kit vs what you are using now side by side comparison to see if they are even close to the same ph results. Also, your tap water has a very high ppm of 400ppm. You are on the cusp of having to go the R.O. route. Starting at 400ppm limits the amount of nutrient you can add by 400ppm. At this stage of veg you should be running around 650ppm nutrient . When you add your 400ppm tap that puts you in the 1050 ppm RANGE. You stated they can't take high ppm but get the environment dialed in and they will be able to handle the higher ppm much better. They look good but they are underfed. Also, waterfall ponics can be supplemented with Air Stones to enhance the oxygen levels in the nutrient reservoirs. I use one large air stone in my 130 qt igloo reservoir and 2 airstones per bucket. I also chill my water nutrient to 68 degrees to ensure oxygen levels are high and root rot is low... Im running dirty with hydroguard to eliminate root rot. So, add air stones to your reservoirs, cool your nutrient with chiller to 68 degrees, lower your ph levels to 5.8 - 6.0 range. Keep relative humidity about 60 percent. Up your nutrient levels (400 ppm tap water + 500 nutrient ppm = 900ppm) then monitor your ppm to see if its dropping every day. If its moving down then the plants are drinking. These are the changes I would make and monitor for change. Good luck with your grow, its totally salvageable so don't tear it all down. The PH is your biggest issue at the moment.
Just double checked, the pen is still calibrated.
Ph is exactly 6.02
Ppm 701
Water temp is 19.5 Celsius/ 67 Fahrenheit

Tap water ph 7.81 / ppm 284
High in calcium
Analysis attached
 

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Does anyone leave the tap water sit for days b4 using
 
My ppm comes out the tap at 80ppm

I just run it threw a chlorine filter before filling my system

I’d recommend an ROfilter or heavy metal filter if your waters quite harsh
 
Just double checked, the pen is still calibrated.
Ph is exactly 6.02
Ppm 701
Water temp is 19.5 Celsius/ 67 Fahrenheit

Tap water ph 7.81 / ppm 284
High in calcium
Analysis attached

I run my chilling system at the same point.
Looks like you will never need cal mag .
 
If your PPM is 701 and your tap is 300 then you are running 401 in nutrient, that is good for early veg but you look like you are weeks into it... you can run hotter if you want to but if you aren't in a hurry......
 
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