Heavy yellowing, from 2-4 weeks in flower. Crop threatened, any advice welcome!

[DixinCider]

just seemed like the plants right under the light seemed most effected. its just a thought. i glanced at the pictures quickly. first i would have thought root aphids, but no bugs. second rot, but your root mass doesnt look that bad. i have seen healthier plants with worse roots (if that is the prob, zone or h202 at there highest dose, its going to spread in the uc)

 

[Reebs]

i would run some fresh balanced water. i forget who said it earlier but it looks like nute lockout at first and now has transformed into this.

as for the roots, they don't look TOO bad to me, usually for me if i see yellowish or close to brownish roots i use straight well water. my water isn't bad though. usually it takes a few days but i start to see new white root growth.

look into hygrozyme and aqua shield,personally when i start to see some yellowing or browning in my aero cloner, i give them like 5ML/Gal hygrozyme and 4ML/gal Aqua shield. seems to clear things right up and gets my roots white again.

- AquaSheild (Botanicare)
-Hygrozyme (like $30-$40/Liter) worth every penny
- Great White Mycorrhizae (Plant-Success) First time using this stuff and i swear by it now. great for cloner's and helps greatly in flowering. basically i've learned that you have to add this last to your water, even after PH up and down. the chemicals from everything will kill the benificial bacteria that is supposed to get into your res and live so it does it's job. it can stain the roots aswell so look closely when examining.

to sum it up the Hygrozyme is the place to start IMO for any root problems when dealing with hydro. time and time again i've proven to myself that Hygrozyme is the shit.

hope this helps

 

[dirk d]

how old is your UC setup?? couple of my buddies had some issues with the tubing. they just couldn't clean everything out and there was a couple spots that just a breeding ground for non-beneficial microbes. might want to looking into swapping out your pvc as a pre-caution. good luck.

 

[Bruce Fever]

@gr33nl3af could it be a ph, nute lock out issue? if ur using a well balanced nute mix it prob wont be a n p or k issue aphids aside. also i had bad issues with jon innis comp for bugs in soil so switched to canna terra, much better. please excuse my ignorance if i am way off here.
@ boylobster... no idea man :( can only think of poor water, sulpher or just inproper sterilisation between runs?
not sure but just some thoughts

 

[Boylobster]

Woah! An explosion of renewed interest! Thanks, all! To address you each in turn...

i would run some fresh balanced water.

, I definitely have flushed the reservoir, but it didn't seem to help, unfortunately. And, even before I did so, and currently, the water chemistry seems really stable. I also strongly suspect microbial activity, but it must not be the kind that causes pH to drop like a rock. As for protection, I just got in some Dutch Master Zone, which is a sterilization agent. I'm not deploying it this run, because I've been using Capulator's Beneficials rather than something like Great White.

how old is your UC setup??

, a very good question. And the answer is, pretty old. o_O Not only that, but more than once, I've not cleaned it quickly enough after a run, and some pretty disgusting muck has formed in the thing in the past. I agree with you - all the plumbing has to be replaced, and the buckets scrubbed and *completely* sterilized. I've got to get as close to starting from scratch as I can.

can only think of poor water, sulpher or just inproper sterilisation between runs?
not sure but just some thoughts

That's where I'm at too. :( As with dirk d, I think as much of the system has to be replaced as possible. Gonna' be a pain in the ass, but... we gotta get this grow show back on track, y'know?

I'll have some more and deeply depressing pics up soon. Thanks for all the continued support - please let me know if you have further thoughts. <3 the Farm.

Cheers,
BL

 

[Smoking Gun]

Ok, so Cap's Benies or Great White, essentially the same thing. Ultimately even if you had bad microbes in the system the beneficial microbes in Cap's mix should have been able to fight them off, rendering that a non-issue. I would also try and talk to Cap about proper use of his Benies in your system with your nutrients, see what he has to say. And from your pics I can see no bugs on the roots, so I would say an infestation issue is also unlikely.

I am somewhat surprised no one mentioned the CO2, as I think this is where you are having problems. Kept everything the same as before but you added CO2, and this changes a lot more than you think. Pumping additional CO2 into the space means your plants are going to grow at a faster rate, which means they are going to use food, water, and light more quickly. While you are not going to run out of light, you will easily run out of stored food in the plant as photosynthesis rate has increased. So I would not be surprised at all if you are dealing with a nitrogen deficiency. As I already stated if you are adding in CO2 your plants metabolism has increased and you must keep up with that increase in metabolism, but it doesn't seem as though you have made the proper adjustments. I would say that you need to increase the strength of your nutrients as your plants are going through them more rapidly.

Another thing to keep in mind is that CO2 supplementation works best when the temperatures are about 85 degrees Fahrenheit. This increase in temperature is also to accommodate the increase in your plants metabolism.

Ultimately you have tried to push the plants metabolism to the max without giving it any extra help to stay healthy. Think of it this way, you can have a world class athlete, but as soon as you decrease their calorie intake and reduce their training regiment, they will quickly be left in the dust by their competition. By keeping your temperature and feeding regiment where it was before the CO2 introduction you have deprived the plants of what they need to perform their best. One small change and everything needs to be adjusted, you have made a relatively large change by adding CO2.

Since you were on week 4 about 3 weeks ago, I would not bump up your nutrient feedings much at this point as I assume you are close to harvest, but keep in mind that in the future you will need to have more food for plants with CO2 supplementation. For the brownish roots, I would use Hygrozyme once every other week at 5-10 mL per gallon. I would increase your temp in the room to between 80 and 85 degrees Fahrenheit. I also would change out the PVC and other tubing just to ensure you have no gunk built up in there.

Hopefully this was of some help to you.

 

[smokie]

Blue Dream will do that to me if i don't give her enough cal mag at the beginning of flower

What is your nute strength?

 

[Boylobster]

Ok, so Cap's Benies or Great White, essentially the same thing. Ultimately even if you had bad microbes in the system the beneficial microbes in Cap's mix should have been able to fight them off, rendering that a non-issue.

Thanks for all the suggestions, Gun. We're troubleshooting here, so please don't feel as though I'm just regular 'ol shooting you down when I address some of your points. ;) I'm familiar with the role of bennies, be it Great White, Voodoo Juice, or what have you. I started using Cap's formula because it has an exceptional reputation on the farm. I too would have hoped the beneficials would overwhelm any unwanted pathogens, but if you'll look closely at this shot from the first page...

...you can see that something ain't right, there. Look at the dark brown slime and necrosis on the larger structures. On one of the worst affected plants, when I lifted the thing up to inspect the root ball, about 90% of the root mass just *fell off*, it was so deteriorated. No joke. So clearly, something is not well with the roots, Cap's Beneficials or no.

I definitely talked with Cap about proper usage, and as far as I can tell, I'm deploying the cultures exactly as per his recommendations.

A couple thoughts about CO2. I considered that I might not be feeding heavily enough, but the nute concentration in the rez never changed, which would indicate to me that I had the concentration of the top-off rez set appropriately. Right? If they needed more, the EC would fall. If less, it would rise, no? And temperatures weren't as high as 85, but have probably been around 80F for flower.

In addition, I drastically cut back CO2 supplementation, in case it was a complicating factor... with no improvement. :( I think the real smoking gun lies in the roots, however. The rootball should not be brown, nor should it simple rip off the plant under its own weight, and I can't see what CO2 would have to do with that.

You mention Hygrozyme. I'm using Multi Zen as part of the H & G line, which is their enzyme formula. I've no idea if they're even roughly equivalent, however. Really, I've decided to just scrap all the hardware in the system and start fresh. Thanks for posting such extensive advice, and let me know what you think of my rejoinder, yeah?

Blue Dream will do that to me if i don't give her enough cal mag at the beginning of flower

What is your nute strength?

smokie, this is the same strain and nute line I work with every run, so no surprises there. Nute concentration is about .3-.4 EC.

 

[Seamaiden]

Mmm... I wish I could link to threads on other forums, but there's a thread on ICM by a fellow who had been battling root rot for ages in his hydro set-up. I cannot for the life of me remember what he finally went to get rid of the crud... let me see if I can find something for you on that.

I can't remember which member, but I'm still searching!

 

[DeanCanna]

th3b12ain: Thanks for the suggestion! Again, I wish it were something so simple... but my other spot used the exact same nutes (I had to lug 'em from place to place : P), and has nothing but pearly white roots. So... I'm not sure that can be the primary factor.

DixinCider: Well... the hoods are air-cooled, and not very hot under the glass. Plus, the symptoms are worst on the oldest fan leaves, well underneath the canopy. Take a look at the pics, maybe? It's a thought, though, thanks!

To anyone else who might roll through, I'm almost entirely certain that this is a microbe/root health issue. Look at the close-up shots of the root mass - browning and die-off on some of the thickest structures.

I've experienced this same issue as well when I took a shot at Grodan and was first implementing co2.. I never figured it out but one theory I had was that I was using ac runoff and I figured that it was unstable, my ph was fluctuating wildly.

From your pictures I would agree that it's a root issue. Have you tried a hard flush or using a enzyme product to assist with clearing out affected roots?

 

[smokie]

Are the net pots choking your roots? are they 5.5 in or 8 in net pots?

 

[caveman4.20]

Root aphids can be systemic sometimes you don't see them and this is the time most people find em jus a lil late but somewhere on the farm I read of caps bennies killing them I believe It mutates there reproductive system but I'd bet the ranch it's a systemic root aphid I bet it's that black super bug that's systemic how you have it at one place and not another is beyond me I wouldn't be surprised if you star having the same problem soon at the other spot tell me is the other spot the same stage of growth and same age?

 

[Smoking Gun]

A couple thoughts about CO2. I considered that I might not be feeding heavily enough, but the nute concentration in the rez never changed, which would indicate to me that I had the concentration of the top-off rez set appropriately. Right? If they needed more, the EC would fall. If less, it would rise, no? And temperatures weren't as high as 85, but have probably been around 80F for flower.

I definitely agree you have issues with your roots, especially if a whole root ball just fell apart. However my comments about underfeeding still stand. You are not wholly incorrect in the assumption that your EC or pH would fluctuate if the plants are using more food or water than normal. However, this only holds true if the plants are using more food than water or more water than food. You can still be underfeeding the plants even though they are using food and water in balance. An EC of .3-.4 seems very low to me for flowering plants, that is the range I would use for early veg. So I still think you need to boost the food a bit. However with your apparent foot issues raising the EC will not help at this point, so just a bit of advice for the future. Hopefully you can get this issue resolved before your next run. New gear probably will not hurt.

 

[Boylobster]

Are the net pots choking your roots? are they 5.5 in or 8 in net pots?

I definitely agree you have issues with your roots, especially if a whole root ball just fell apart. However my comments about underfeeding still stand.

smokie, you could argue that the pots aren't large enough, but keep in mind that I've been running this *exact* setup for a couple of years. Same system, same mother, same wattage, same water source, *everything*. This problem is unique to this run.

Smoking Gun, I hear you on the nutes, now. All the steady EC means is that they're being taken up in balance with the water. Gotcha'... and it *is* interesting that some of the sturdiest, most aggressive plants seem to have been the first and worst affected. However, I've got to point out what I told smokie, and that's that while that nute strength might seem low (and I know it is compared to many), I've done pretty damn well with this formula in the past. My peak efficiency with this system, low nutes and all has been 1.3g/Watt over an 8-week flower, or to put it another way, 1lb/sq.ft. I'm not at all boasting - I only want to illustrate that what has been very successful in the past is suddenly not working.

This poor cat describes symptoms very similar to mine: https://www.thcfarmer.com/community/threads/how-i-defeated-pythium.35614/

So... perhaps pythium? Even assuming underfeeding relative to CO2, that doesn't explain the horrid state of the roots. Solution? Fuck cleaning; it's time to upgrade. All-new plumbing, pump, tent, buckets, and a bump up to 4x1000W. Maybe this shitty run will be the best thing to ever happen to my grow. ;)

 

[Seamaiden]

When you can't figure something out, go back to the basics. Right now, if I were in your position, I would be looking at that source water. It's your biggest variable right now. UV sterilization would resolve many issues for anyone running hydroponics. The only concern I personally would have is whether or not the UV could cause some other sorts of reactions with the nutrients that are in solution as well.

If you're on a muni supply, and forgive me if we've already discussed this, but I've had this same discussion repeatedly over decades, then it's very possible that the source water's quality has changed, and possibly quite significantly. Perhaps enough so that something has been able to take hold in your system.

 

[Boylobster]

If you're on a muni supply, and forgive me if we've already discussed this, but I've had this same discussion repeatedly over decades, then it's very possible that the source water's quality has changed, and possibly quite significantly. Perhaps enough so that something has been able to take hold in your system.

Mmm... no municipal supply, and neither you nor anyone else has asked that yet either, so all is forgiven. ;) In fact, a prize to you for suggesting new factors! No, I get my water delivered from a company that pulls it straight out of an enormous natural aquifer, so the chances of a significant change in water composition are slight.

I really think that after years of running the same pipes in this system, and on several occasions having allowed some serious post-harvest rot to take place before trying to thoroughly clean the thing... I think I may have finally bred something hardy enough to be a persistent problem. For example, despite running massive amounts of bleach through the system between the last run an this, when I replaced the 3/4" pump lines, they were still choking full of a light grey-green-brownish sludge.: P It's going to be a pain in the ass, but I'm actually looking forward to starting over clean. I'll get some more pictures up tonight, so y'all can see just what this has done to my poor babies as we near the end of flower. :(

And again, I sincerely apologize if it sounds as though I'm just shooting everyone down - I'm only trying to build as complete a picture as possible. I really do appreciate the consideration and advice. Thanks again!

 

[entropy99]

That root rot does not look good. Have you ascertained whether there is a fungal pathogen present?

 

[Boylobster]

That root rot does not look good. Have you ascertained whether there is a fungal pathogen present?

As in had lab work done? No. It seems clear that there's one or more invasive organisms of some kind at work, but that kind of specificity hasn't been achieved.

 

[Seamaiden]

Bleach is not a kill-all disinfectant. Reconsider the cyanobacteria issue, as well as the source water. Aquifers are supplied from somewhere, and it's perfectly feasible for water quality to change, though presence of pathogens is less likely unless weather patterns are greatly changed in your area--that will have an effect on water quality unless it's distilled or highly filtered.

 

[Boylobster]

Hm. Heard you on the bleach. Well, I *am* turning that aquifer source water into RO product via a 5-stage Reverse Osmosis system... or are we talking lab-grade filtration here? Without having before and after analysis done on the source water, I can't say much about any changes in it's composition, however, I have measured its EC and pH from time to time, and that never varies.