Hydroponics

So, I have 2 plants in a DWC bucket. One is doing fine, other has, I have recently noticed, sterted having new leaves curl downward at the edges (I think it's called the claw). They are dark green color with area where they curve tinted almost purplish.

They are almost 4 weeks old, under CFL-s, res temps are at about 60 to 65, pH is in 5,5 to 6,5 range. EC is about 800 uS (3/4 recomended dose for advanced hydroponics dutch formula nutes). I suspect some kind of nute burn (nitrogen toxicity) and will be giving that plant new home in its own bucket with nutes toned down to perhaps 600. I was wondering if you guys have any thoughts on other possible problems I should consider that cause similar symptoms.

Combining esoteric energy sources (read not taught in schools) I put together what I call a High Performance Rez

It combines a ~ 400 gph pump circulating the nutes 24/7. The nutes pass through 2 magnets in repulse, then splash over a colander filled with polished ornamental rock, which sits above the water line. The purpose is to duplicate the chi (measurable energy) that fast moving water cascading down a stream creates.

A small (160 gph) pump feeds the plants every 45 minutes during lights on; 1:45 during lights off.

Both pumps sit on 4" air stones mostly to keep them from floating, creating massive DO.

Pic that shows the 2 clones on the drain table were taken 12/25~

Spanky84 said:

So, I have 2 plants in a DWC bucket. One is doing fine, other has, I have recently noticed, sterted having new leaves curl downward at the edges (I think it's called the claw). They are dark green color with area where they curve tinted almost purplish.

They are almost 4 weeks old, under CFL-s, res temps are at about 60 to 65, pH is in 5,5 to 6,5 range. EC is about 800 uS (3/4 recomended dose for advanced hydroponics dutch formula nutes). I suspect some kind of nute burn (nitrogen toxicity) and will be giving that plant new home in its own bucket with nutes toned down to perhaps 600. I was wondering if you guys have any thoughts on other possible problems I should consider that cause similar symptoms.

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Im a relative newbie when it comes to hydro, With limited knowledge in the area fyi. Just getting ready to start my first full scale hydro-grow so im still learning as I go. I did notice though that you didnt specify how frequently you are changing the reservoir? It could be as simple as your nutrients being out of balance if the res. isnt changed frequently enough. I could be way-off, Like I said im pretty new to hydro but that would be the first thing that i would want to check. I apologize if this wasnt helpful, Just didnt seem like you were getting answer from anyone else so far. I asked a question about nute brand preference for a led+hydro setup about a week ago and nobody has responded, So I thought I would try to give you a possible answer. I also remember someone telling me that a copper deficiency can cause leaves to turn purple and curl near the edges, If that helps at all.

Thanx

I'm changing my res every 7 days so that shouldn't be a problem.
I have put my plants in separate buckets yesterday and given the "sick" one a bit less nutes. Now it has only 600 uS while the other one gets 800 again. I hope I'll be seing positive changes by tomorrow...

Spanky84 said:

Thanx

I'm changing my res every 7 days so that shouldn't be a problem.
I have put my plants in separate buckets yesterday and given the "sick" one a bit less nutes. Now it has only 600 uS while the other one gets 800 again. I hope I'll be seing positive changes by tomorrow...

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Spanky84, I did a little looking to find a remedy to your current issue with the color change and curling of the leaves. I did come across an article here on rollitup that might be of interest. Hope this helps if the problem is not yet under control. Try reading this and see if it applies. https://www.rollitup.org/marijuana-plant-problems/413859-curling-purple-red-stems-purple.html

Hope you get it figured out before things take a turn for the worst. Ill keep an ear out for other solutions unless I see a post saying youve got it under control. Good luck.

Regarding res changes I again am far from a hydro expert but I would think a change every 7 days is more than adequate. I would think changing any more frequently would simply be a waste of nutrients.

Spanky84, Came across this a minute ago and thought it was worth posting. Not sure it will answer your question but is handy.

View attachment 2983827

Yep, looks like too much nitrogen.

Glad to hear you identified the problem, So cutting back the nutes on that plant like you did should rectify the problem. Hopefully the damage isnt severe and it will spring right back.

Glad to hear you identified the problem, So cutting back the nutes on that plant like you did should rectify the problem. Hopefully the damage isnt severe and it will spring right back.

She is at 500 uS and is showing healthy new growth already.

Congrats, Youre legitimately 1 step closer to being a Pro-Grower. Glad to hear everything is working out. We all know how crushing it can be to lose a plant, Especially if the strain is hard to come by.

Its odd though that both plants were in the same dwc system and only 1 fell ill. Were they both the same strain? If not then that would explain it as different strains are more/less susceptible to various factors.

Nope, very different strains.

I was planing on separating them once they got a bit bigger, but it turned out one plant was sensitive even to lower then recomended nute concentrations I fed my plants. Whats suprising is that it is the plant that by comon knowlidge is a more heavy feeding strain.

Spanky84 said:

Nope, very different strains.

I was planing on separating them once they got a bit bigger, but it turned out one plant was sensitive even to lower then recomended nute concentrations I fed my plants. Whats suprising is that it is the plant that by comon knowlidge is a more heavy feeding strain.

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Keep in mind there is always the chance you didnt receive the strain you expected. With clones/cuttings its notoriously difficult to get true strains a lot of the time. And even with seeds its not always a guarantee, Especially if its not from a reputable supplier. I had ordered some beans of a specific strain once and it was clearly the wrong strain, I had ordered from nirvana and they were really cool about making it right. Didnt change the fact that I wasted effort growing a strain I didnt want in the first place.

Sometimes they are just finicky though. A while back I was growing a pre-86 blueberry strain and was having a hell of a time feeding it, It just didnt seem to be doing well at all. I tried adjusting nutrients, lighting, etc. and just couldnt get it to grow well. At the time I had gone a bit overboard and had approx 10 strains going (way too many to grow right) I ultimately decided to thin down the strains and regrettably the pre-86 was one of them. My little bro ended up snatching the 2 plants i had growing of it to see if he would have any better luck. He immediately began triple dosing the nutes! I told him he was nuts and would surely kill them, without a doubt. A week or so went by before we spoke again, And again I stressed to him that they would die if he kept it up. Long story short by some fluke he actually managed to crop them both out quite successfully! Not sure how as it defied everything I knew and had been told about the strain, And im quite sure If i had tried that it would have been disastrous. Just because we think we have something figured out, Doesnt mean we are right!

What are the ideal temps for hydro and are they different form soil techniques? My temperature sensor shows 31C (87.8F) (goes down to about 28C (82,4F) when I make a little tin foil roof above it so its not directly exposed to the light). From what I understand that is a bit high for soil, but since my plants can take as much water as they need from the DWC bucket, am I OK, or should I be investing in some more fans?

At the moment I have a 105 m3/h intake fan blowing at the plants and a 300 m3/h exaust fan pulling the air through a carbon filter, through a cool tube cooling my 400W HPS and out of my 1 square meter box.

Spanky84 said:

What are the ideal temps for hydro and are they different form soil techniques? My temperature sensor shows 31C (87.8F) (goes down to about 28C (82,4F) when I make a little tin foil roof above it so its not directly exposed to the light). From what I understand that is a bit high for soil, but since my plants can take as much water as they need from the DWC bucket, am I OK, or should I be investing in some more fans?

At the moment I have a 105 m3/h intake fan blowing at the plants and a 300 m3/h exaust fan pulling the air through a carbon filter, through a cool tube cooling my 400W HPS and out of my 1 square meter box.

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Again not a hydro expert, But I believe the "Sweet spot" is 65-68F. Any warmer and you will be battling with bacteria in the reservoir. Also at temps over 70F the nutrient solution in the reservoir will absorb/hold less oxygen as temps increase. At 68F you have the most oxygen content as well as the lowest risk of bacteria and mold. Also fyi, Your reservoir should not be exposed to direct light as this will not only affect temps but encourage bacteria and algae growth.

To clarify what are your res temps and what are the room temps?

If your res is close to 90 degrees than your grow room must be Scorching! That or your pump is way wayyy overheating the res.

Room temps. Res temps are at 16 to 19 C (60 to 66 F), well hiden from the lights.