DWC Plants Dying Please Help

[QuindariousGooch]

IMO your ppm/ec may be too low. Try top-feeding with 500-600 ppm and see if they start to open up and stems start greening. I've seen heat and low humidity shut them down like this too but you have that dialed in. I would be interested to hear what happens if you try the top-feeding to "wake them up". If that works increase the reservoir. You might even push the ppm's on 1 plant to see if more is better in your system.

For reference on using higher ppm...
We pop seeds and start clones in 1250ppm (500 scale) in rockwool. We run veg and moms on the same water. Our best results on popping seeds was 1000 to 1300 range...We soak the block in it initially, place the dry seed into and A-OK and put that into the 1250ppm soaked block. Then we water 1x daily with 1250ppm. No humidity dome for seeds and we put them in the same light the moms are getting. Used to be HID and HPS but now we are LED in clone and veg. The seeds will adapt to whatever environment they pop into. The key is keeping them watered. They can take all the light you can give them if they have the transpiration rate to handle it.
Before anyone calls bullshit on the above process I encourage you to try it. I only mentioned it to give an opening to the idea that higher ppm than the charts say can produce better results. I realize I'm a rockwool grower and DWC is known to be different...but what if it's not so different? What if higher ppm's are better in this case? I'm not saying this is the answer rather give it a try/test.

For reference we run 1300-1400 clones every 2 weeks and 20-50 seeds (or 1-2 cultivars) every 4-6 weeks. All clones & seeds are run at a minimum of 1250ppm right out of the gate and continue through the veg cycle. I won't even mention what ppm we run in flower but it's "a bit" higher than 1250ppm. I used to get great results in coco pearlite at 600-1000 max and used to be skeptical about higher numbers so I understand growers who might push back on this methodology. I welcome debate if it is based on data and testing. Opinions are fun to listen to but I have learned to test all changes vs immediately implementing because it seems to make sense. Free advise is worth what you pay and should always be vigorously vetted based on the downside risk. That's why I suggested the top feed vs bumping the whole rez up. See what happens on 1 plant. If it works or doesn't you have learned something.

Iron sharpens Iron... Let me know if you try it and if so I would love to hear your results.

Cheers,
Q

 

[Scolymia7]

I would agree ppm is really low, also rez temp. I get sterile, but when they are that young and still building roots, I got best results with air temps around 80-82°, and 60-65% humidity and rez between 75-77°. You are also running sterile water(h202) so maybe hold off on the low 60s till you get later into flower. In dwc mine was always around 75 since I used bleach. Yes bleach can be used and plants do just fine. Tons of research, knowing exactly how much water is in system, and having a reliable ppm meter. I used ppm to measure how much bleach was added. Rez always smelled clean, roots exploded, and never any slime build ups or root rot.

The top feeding idea is good. Its what I did when first putting rooted clones in to the dwc system before letting pumps run on timers. Id top feed 2 times a day for a few days. I also kept covers over base of stem/ the pots to prevent quick drying of clay pebbles. After that normal flood and drain feeding schedule. Usually by then I was noticing Rockwool almost being sucked dry between feedings.

I'm not sure how to attach links but if you Google led grow temps and find a link to black dog grow theres some great information on keeping higher air temps with leds. My air temps running hlg550 are 82-84(kept leaf temps at 78-80), and humidty 60-65(not perfect vpd). I dont run c02 so don't go higher. Thats all the way until week 3 or 4 of flower. Then I drop temp/humidity because I've had bud rot and pm before. And I want to somewhat mimic nature in making the plant thing "winter is coming". So then temps are 76-78(leaf temps 76-78), and 55-58% humidity.

Oh and to save some watts, your 12k ac is a wee bit large for your room size. My room is 2.5× the size of yours and I run a little 5k btu. Bigger unit makes more humidty because it cant run correctly causing your dehumidifier to run more and not give you the best long period control of air temps and run up electric bill.

Hopefully you get everything dialed in, you got a nice little build going on there!!!

Happy Growing

 

[MHippie]

Alright so idk what in the world is going on.
Its been a week and still little to no roots out of the rockwool at all.


They are beginning to droop, and continuing to twist. Purple stems, very little upper growth as well. The only thing I noticed was the 2 small aqua fans were blowing on the plants, maybe making them droopy? However the fans have been off for 12hrs and stilll no improvement To the droop

I can for the first time today, officially see some roots just starting to pop out of the bottom of the 1st netpot.

I’m really hoping in the next 24 to48 hours they start to explode....

Then again... I thought that was going to happen a few days ago.

I don’t honestly know what’s going wrong here.

Water/nutrient solution is still good at
64F
250ppm
5.6ph

Room climate holds a steady 40-50RH now at 75F

Light is 42” away at 25% intensity

Ok... hmmm... well imo if it was a nute deficiency then it would be expressed differently. They just look thirsty.

Here's an easy way to figure it out.

Prepare a shallow container with your nutes. If those were mine, I'd do the 4 tbl per gal Clonex solution to promote root growth. Drop the pots into the container so that the first inch or so is covering 1/2 of the rock wool cubes. The hydroton will wick up that water too. Pour some over the top of the pot, not the plant. If you have some clear ph balanced water in a spray bottle, then mist them. Flip your fan on low and don't aim it directly at the plant. You want air movement with limited air flow. Let them rest there for about an hour. See if they perk up. If it is just thirst like I believe it is then they should stand to attention.

 

[Aqua Man]

IMO they are cold and its environment. As I said before I dont agree with low res temp like 64f. Get the res temps up to 70-74f reduce the light as much as possible until they recover, raise the air temps to 80 and up the humidity to 65%.

Just my thoughts fwiw.

 

[FourthCity]

I still think its the rockwool getting too wet because its not positioned correctly in proper netpots.

 

[Aqua Man]

I still think its the rockwool getting too wet because its not positioned correctly in proper netpots.

I agree but I feel its because of environment. Like a cold rootzone in soil...they just don't drink well and that can leave the rockwool wet and plant looking over watered. If you look at his VPD the KPA is suited to that of a mature plant in flower. So essentially water stress just as you would see in a soil grow.

 

[Aqua Man]

@FourthCity I agree the cube placement is not at all ideal and contributing. Should be 1-2" of hydroton under the cube.

 

[FourthCity]

I agree but I feel its because of environment. Like a cold rootzone in soil...they just don't drink well and that can leave the rockwool wet and plant looking over watered. If you look at his VPD the KPA is suited to that of a mature plant in flower. So essentially water stress just as you would see in a soil grow.

@FourthCity I agree the cube placement is not at all ideal and contributing. Should be 1-2" of hydroton under the cube.

I agree about the environment too, its really both these issues together that are causing major harm. Its kind of like being outside in wet clothes in cold weather, fixing just one of those issues would offer a huge improvement but fixing both would be ideal.

 

[chemistry]

The cuttings were potted up on Friday, it will take a couple of days for the roots to get going again.

 

[TheOhmOne]

IMO they are cold and its environment. As I said before I dont agree with low res temp like 64f. Get the res temps up to 70-74f reduce the light as much as possible until they recover, raise the air temps to 80 and up the humidity to 65%.

Just my thoughts fwiw.

the light is 42” away and on 25%

The temp in the room averages over 75
Humidity is holding pretty steady over 50% now as well.

I do think the root zone may be too cold, but only because they are so small still. However it’s never been a problem before...

As far as netpot placement.
The rockwool cubes are essentially floating 2-3” above the bubbling water line. What is wrong with this exactly ?

The water temp is 64f but the air above and inside the netpot is not.

 

[Aqua Man]

the light is 42” away and on 25%

The temp in the room averages over 75
Humidity is holding pretty steady over 50% now as well.

I do think the root zone may be too cold, but only because they are so small still. However it’s never been a problem before...

As far as netpot placement.
The rockwool cubes are essentially floating 2-3” above the bubbling water line. What is wrong with this exactly ?

The water temp is 64f but the air above and inside the netpot is not.

Because the rockwool will stay fully saturated.

 

[FourthCity]

The rockwool needs to be surrounded by the hydroton because the pebbles are key to managing the moisture. If the rockwool is too wet than the hydroton will soak up the excess water but if the hydroton is too dry it will absorb moisture from the hydroton around it. When the bottom of the rockwool is exposed to the bubbling water from the dwc you severely limit its ability to drain excess moisture and breath properly. Think of the hyrdoton as like a straw for the rockwool, all the moisture coming to the rockwool should go through the straw.

 

[QuindariousGooch]

I still think its the rockwool getting too wet because its not positioned correctly in proper netpots.

I have had clones in Rockwool that got left on a counter for 1 to 2 weeks and the plant still didn't look bad. They do look a little overwatered but I don't do DWC so I was hesitant to say anything but along with the res temperature I think it makes sense

 

[TheOhmOne]

IMO your ppm/ec may be too low. Try top-feeding with 500-600 ppm and see if they start to open up and stems start greening. I've seen heat and low humidity shut them down like this too but you have that dialed in. I would be interested to hear what happens if you try the top-feeding to "wake them up". If that works increase the reservoir. You might even push the ppm's on 1 plant to see if more is better in your system.

For reference on using higher ppm...
We pop seeds and start clones in 1250ppm (500 scale) in rockwool. We run veg and moms on the same water. Our best results on popping seeds was 1000 to 1300 range...We soak the block in it initially, place the dry seed into and A-OK and put that into the 1250ppm soaked block. Then we water 1x daily with 1250ppm. No humidity dome for seeds and we put them in the same light the moms are getting. Used to be HID and HPS but now we are LED in clone and veg. The seeds will adapt to whatever environment they pop into. The key is keeping them watered. They can take all the light you can give them if they have the transpiration rate to handle it.
Before anyone calls bullshit on the above process I encourage you to try it. I only mentioned it to give an opening to the idea that higher ppm than the charts say can produce better results. I realize I'm a rockwool grower and DWC is known to be different...but what if it's not so different? What if higher ppm's are better in this case? I'm not saying this is the answer rather give it a try/test.

For reference we run 1300-1400 clones every 2 weeks and 20-50 seeds (or 1-2 cultivars) every 4-6 weeks. All clones & seeds are run at a minimum of 1250ppm right out of the gate and continue through the veg cycle. I won't even mention what ppm we run in flower but it's "a bit" higher than 1250ppm. I used to get great results in coco pearlite at 600-1000 max and used to be skeptical about higher numbers so I understand growers who might push back on this methodology. I welcome debate if it is based on data and testing. Opinions are fun to listen to but I have learned to test all changes vs immediately implementing because it seems to make sense. Free advise is worth what you pay and should always be vigorously vetted based on the downside risk. That's why I suggested the top feed vs bumping the whole rez up. See what happens on 1 plant. If it works or doesn't you have learned something.

Iron sharpens Iron... Let me know if you try it and if so I would love to hear your results.

Cheers,
Q

Honestly I find your feedback very interesting,

I can never seem to push the plant up to even 1kppms.

The ppms are low here,but that’s isnt really the symptoms they are presenting.

I’m perplexed here, I will try upping the ppms, I’ve got nothing to lose

 

[TheOhmOne]

I still think its the rockwool getting too wet because its not positioned correctly in proper netpots.

The rockwool is not too wet, if anything it is too dry, but I am top feeding when I notice it’s getting dry.

Do you really think the rockwool sitting 2-3” directly above the bubbling water line is causing issues ?

 

[TheOhmOne]

The cuttings were potted up on Friday, it will take a couple of days for the roots to get going again.

Should they really be dropping and twisting like this while rooting ?

I feel like normally the growth is just slowed while rooting, but nothing ever really dies or looks this terrible

Would I be better to take my own cutting and root them in with a collar in an areo cloner ?

 

[chemistry]

With the roots you have on your cuttings, I'd go 500ppm at a PH 6.0, no fancy additives, just base veg nuits until your cutting start to rock n roll.

 

[chemistry]

Should they really be dropping and twisting like this while rooting ?

I feel like normally the growth is just slowed while rooting, but nothing ever really dies or looks this terrible

Would I be better to take my own cutting and root them in with a collar in an areo cloner ?

You have to leave them in the pots to grow and not take them out, as every time you do this, it knocks them back a couple of days. Plants don't like their roots messed with. The dry rockwool is not a problem as long as your roots can drink.

 

[Scolymia7]

Another thing to consider is you have your leds dimmed to 25%. Ive read mixed reviews on dimming leds and the spectrum changes. Your brand lists it to be hung greater than 6inches(didnt specify at what % power) and yours are hung 42 inches.

Maybe bump up to 75% or if you wish to keep them at 25% lower them to 6-10 inches above canaopy. Could help boost your leaf temp just by lowering. At 100% my leds are about 16inchs from canopy.

Outside of nutes being low your temps are low. Usually your leaf temp will be cooler than ambient temp. So if your temps are around 75° your leaf temps are going to be lower. Which is too low.

 

[FourthCity]

Do you really think the rockwool sitting 2-3” directly above the bubbling water line is causing issues ?

My issue is less about how far away the rockwool is and more about the lack of hydroton for drainage underneath it. Water should only be absorbed into the rockwool through the hydroton not sprayed directly on it, the hydroton will naturally regulate the moisture for you. I'm promise I get no enjoyment out of repeating myself I only keep saying it because I think it will really help.