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Grow/Environment Help

Hey Guys,

So I am going to start the forum off with its first help topic… and so far, it’s been a doozy of a problem. Any input or past experience would be a huge help and greatly appreciated. If you make it through this big ol’ story problem - I thank you in advance.

Here is our situation:
We are having yellowing/drooping of our leaves about 5 weeks into veg, it rebounds and greens up, and then shows itself again about 5 days into flower… But this time even more yellowing and drooping and it never seems to fully turn around throughout flower. We grow in a fully sealed warehouse with Co2 supplemented. Full environment info listed below.

So here is our setup starting from clone:
-Our clones are taken from mothers or other mature plants in veg and put under T5 lighting (no problems at this phase).
-Once we have roots, we then repot straight into 1 gallon pots and they are put under 315 watt lights on the second tier of our 2 tier shelves. The 315’s are probably about 4 feet from the canopy in this stage. At this point, they are lush green and seem to be doing great.
-A couple weeks into those 1 gallon pots and under those 315s OR right when they get repotted into 5 gallon pots and put under 600w MHs, we start seeing a little yellowing and some droopiness. (level of yellowing/drooping has varied at this point depending on cycle/strain).
-Once they are put in 5 gallon pots, they are placed under 600w MHs on the “ground level” (or first tier) of our shelves. Lights are about 3-4 feet from canopy in this phase. Usually the yellowing has taken place or starts to take place at this stage. We get the plants to rebound in about a week or two while still in veg.
-We then move the girls to the flower room. They are placed under 1000w DE Gavitas with the light output level turned down to 65% or 650 watts. For the first few days, they look beautiful. Lush green and reaching for the light.
-After about 3-5 days in flower, the drooping begins. The drooping is similar to that of a plant that needs water, although the leaves look much heavier and don’t have the flimsiness of a leaf that needs water. About another 5 days after that, the yellowing starts in again.
-The plants continue flowering with buds forming and growing but the leaves just never seem to come back and the overall look of the room is rough. Premature yellowing and dead leaves throughout flower and the drooping never seems to fully subside.

Our environment:

Veg Room
Fully Sealed Room w/ Co2 supplemented.
83 Degrees Fahrenheit
50-55% RH
Co2 supplemented to 1,100ppm

Flower Room
Fully Sealed Room w/ Co2 supplemented.
77 Degrees Fahrenheit
45-50% RH
Co2 supplemented to 1,100ppm
30 Gavitas in 24’ x 36’ room (6 x 5)
25 tons of a/c. (5) 5 ton ductless units.

Ideas we’ve considered to be causing the problem:
-Shock from the Gavitas in flower. This is why we are now starting them off at 65%/650 watts per light.
-Humidity issue. Our humidity was originally running at about 37%. We added 2 commercial size humidifiers/vaporizers to bring our humidity to its current levels in veg and flower.
-Root rot. To begin with, we found that we had too much Chlorine in our water supply. We quickly changed to R/O water and now oxygenate/warm it to the perfect temperature. However, our original plants were already hit with the bad water and seemed to lock the plant from drinking. It has been a slow rebound but we now see minor yellowing on plants that were never hit with that water. Also to note - we are currently using Veg+Bloom r/o as a nutrient and Cal-Mag.
-After we started using R/O water, we thought it may be a Cal-Mag deficiency because the yellowing in veg looks very similar to that of a cal-mag deficiency. Adding cal-mag didn’t seem to help our problem.
-Co2 levels too high during the dark cycle. We aren’t sure if this would really negatively impact the plants but its a fairly simple fix so we thought we’d give it a shot. Right now our Co2 levels are 950+ at night. We are currently working to use a ceiling fan at night to remove the Co2 and see if there is any change.
-Too much A/C? Possibly creating a vacuum effect? This probably would be a tough fix but it’s something that has crossed our minds.

I plan to post plenty of pictures tomorrow to give everyone an idea of our setup and the look of our plants, but I wanted to at least put this out there in the off chance that someone that reads through this has had a similar experience and would know a solution to our problem so that we could get on immediately. I at least have one picture to share today that shows how the plants looked after being in flower for about 5 days.

Any ideas would be greatly appreciated. Our team combined has had years of experience and it is just driving me crazy that we cannot pinpoint the problem. Thank you guys so much and please let me know if you have any questions.

Thanks again,



This is an extensive issue. Likely there is an interaction between moisture content and the fertilizer program. I will need a lot of details on how often you are watering, how much, fertilizer strength, how much drainage, etc. if you can lay all these details out as clearly as the first comment then I can give you some real feedback.


I agree with Shane. This is complex. Can you give us a more detailed nutrient regimen and watering schedule. Run off tests and what medium you are growing in? Hopefully we can all sort this out. How quickly do they dry?


Thank you guys so much for your responses. I will try and give as detailed of a response as possible for exactly what we have done over the last 6 months of dealing with this issue.

Starting from the beginning:
I wont spend a lot of time on our past program, but I figure it may help give everyone an idea of the complete situation.
To begin with, we were using the Heavy 16 regimen. It was our first stab at synthetic nutrients. Our medium was and still is a Coco + Perlite mix (80/20). We at first PH’d to 6.1 - 6.3 but adjusted to 5.9 - 6.1 because Heavy 16 is a synthetic. We were watering a 1/2 gallon when they first hit 5 gallon pots and 1 gallon in late veg and into flower. Plants in 1 gallon pots were getting a couple cups of water with the standard Heavy 16 feeding. We watered everything as the pots dried up and became light. We were having the same issues in flower at this point but thought we had figured out the culprit at the time (the chlorine in our water and possibly the intensity of the lights in flower). We switched to Veg+Bloom about 3 months ago and it is currently what we are running.

The start of Veg+Bloom:
As stated above, we started Veg+Bloom R/O formula about 3 months ago. We stuck to our ways of 5.9 - 6.1 PH, EC between 1.6 - 1.8 prior to watering and watered the plants the same amount as listed above. (1/2gal - 1gal for the 5 gallon pots, a cup or 2 for the 1 gallon pots depending on plant size). We would first add Cal+Mag to 0.2 EC, 5g/gallon of Veg+Bloom and 1g/5 gallon of +Life (plant probiotic). We at first used Shine (Bud Booster) in the first week of flower as it is called for in the Veg+Bloom feeding chart and brought the Veg+Bloom base nutrient down to 4g/gallon but noticed yellowing yet again. We decided to cut the Bud Booster out and stick with a full 5g/gallon in hopes that the base nutrient would give more nitrogen and keep the leaves from yellowing so quickly into flower. We have yet to bring Shine back into our lineup. Our problem had continued at this point and plants seem to only be needing water about every 5-6 days, even late into flower. This prompted us to test our runoff and make our first change.

What we’ve adjusted since the beginning of Veg+Bloom
-We tested our runoff water and our EC was coming out at about 3.2. As state above, our plants seemed to stay pretty heavy and not require a watering until 5-6 days later. Also, each cycle seemed to have plants that would need to be watered before others. However, these plants did not look any better health wise. At this point we weren’t sure if it was due to potential root rot or root lock from the chlorine that was earlier found in our water. However, this prompted us to decrease our water amounts to make our waterings more frequent.
-We started using a mychorrizae at each repot to help root growth. We however, do not water it in, we sprinkle it in the pots or make a mix to rub on the roots of the clones.

Current Watering/Nutrient Regimen
-Medium: Coco + Perlite (80/20)
-4-5ml/gallon of Cal+Mag
-5g/gallon of Veg+Bloom R/O base
-PH to 5.9 - 6.1
-EC to 1.6 - 1.8
-Mychorrizae at clone to pot and at repotting
-Watering late flower 1/2 gallon every 3 days (dryness/lightness is felt at this time)
-Watering early flower 1/3 gallon every 3 days (dryness/lightness is felt at this time) Soon will be every other day.
-Watering late veg (5 gallon pots) 1/4 gallon every 5-7 days (dryness/lightness is felt at this time)
-Watering early veg (1 gallon pots) 1-2 cups every 3-6 days depending where they are at in veg (dryness/lightness is felt at this time)
-Roughly 10% runoff
-I will test runoff @ next watering and post the results here.
-Our plants currently sit on mesh metal bench tables in flower so our runoff runs to the ground. As for veg, our tables are slightly slanted to drain the runoff to the end. Very little runoff occurs in veg.

Thank you guys again for taking the time to help and if you need anymore information, just let me know.



In coco mediums you shouldn’t be letting them dry in between waterings. Normally you should be hitting them at least once a day. It sounds like you’ve created some root issues. Run off is super important. In coco you should be getting at least 20 percent of what you are putting in running out of your pots. You have to treat coco like a pure hydroponic medium. Your run off is very high. I have a similar set-up although I use pure coco and grow very large plants in 2 gallon pots. This allows for multiple feedings per day and a stable ph. I try to keep my run off within 100 to 200 ppm of the feed. The fact that your run off is so high and all the issues the plants are exhibiting leads me to believe that you are experiencing a two pronged issue that’s is going to make it kind of difficult to recover from in flower. Bad root structure and a salt build up/ ph lock out. I would flush your medium with a 5 g per gallon and .2ec cal mag water until your runoff is equal to the nutrients you are putting in. Once you are nearing that threshold I would do a final feed with life included. You have to let you pots dry an it to allow the roots to recover and begin uptaking efficiently or else the whole issue will recur. Improving on this situation is going to be a balancing act so keep us posted. I would consider making some changes to your protocol and using smaller pots in your future runs. Also consider dropping your ph a bit to 5.7 or 5.8


Sorry for the short answer but feel free to let me know if you have any other questions or clarifications. You can also do a slurry test of your medium to gain a more accurate idea of the ph in your pots.


How are things going @oneofakindgenetics? Any improvements, changes or other news?


Definitely a compound issue here it seems. What are your night time temps and humidity? What are your current run off numbers? Have you scoured the soil for any sorts of bugs? Judging by the runoff numbers you posted, you could be experiencing salt build up in the rootzone. This can be made worse by the fact that these are recently introduced to flowering (I have often seen similar problems with plants recently flipped, especially if the intensity changed.) Also, how much cal-mag are you adding?

I’d make sure your temps are stable through the night, and your root zone is warm enough. Also, carefully check your soil for any mites/bugs. The gardens I have seen this in have had springtails heavily and usually russet mites. Flush with a light mix that is ph adjusted until you get a run off equal to what you are flushing with and then feed it once with the proper food and then let it dry until you’d normally water again. Make sure the root zone has a chance to dry out some (not bone dry, but not soaked) and make sure they never sit stagnate. If this is a continual problem when you introduce the plants to flower, then I’d recommend decreasing the light intensity and matching the environment from the veg room exactly and then ease them over to full flower mode.

Can you give us an update?


This appears to be a toxicity issue related to the growth cycles of the plants. There are two things in common after your changes that I see, which have not been addressed. Medium and water.

Are you, by any chance, in a smaller community that uses a municipal well source, or in a facility which had older, metal plumbing?


Great points Miles. With a runoff reading of 2200 pm when you are feeding half that indicates serious salt buildup, and a perfect recipe for nutrient lockout, making for sick plants. That’s why we recommend recirculating nutrient delivery.


Hey guys,

I want to give a big thanks to everyone that responded and gave us feedback. It has really helped us pinpoint where to focus and really confirmed what we were feeling was the issue.

Here is what we’ve done and where we are at:
-As many of you have suggested, we flushed the plants until our runoff was equal to what our flushing mix was. While our runoff wasn’t as high as it was previously, it was still much higher than it should have been which let us know we were definitely barking up the right tree. A much needed flush started us down the right track.
-The plants took some time to dry up (likely due to nute lockout/the roots just being pissed off) but we have adjusted our nutrient regimen and with a few waterings under our belt after the drying of the flush, the problems seem to be clearing.
-We have put our first cycle since our first post into flower just 2 days ago. I will post some pictures of our new flowering plants in about a week as that was the time we would start seeing issues.

Again, I really want to thank you guys for taking the time to give your $0.02. After dealing with similar issues over the course of a few cycles, it’s hard to remove yourself and look at the big picture. Hopefully now we are back on track (it definitely looks like it but i’m not counting my eggs before they hatch this time!) and we will have beautiful pictures to share with you all in the future. Thanks again and happy growing!


Hey Casey,

I posted an overall update but wanted to answer you back directly to cover all bases.

Night temps: ~69 degrees
Night humidity: ~60% or less

We did check for bugs in our soil. We were thinking potentially root aphids but couldn’t find anything with the microscope in the soil or on the roots. I’m not 100% sure of what “caused” the lockout but there is no doubt that we were experiencing a pretty good salt buildup that effected root development. I will be keeping a good eye on our waterings for the weeks and months to come… Let me know if you have any thoughts and thanks again for your feedback!!!


Hey Joe,

Thanks for the feedback. We are not on a municipal well source but we could potentially have older plumbing. Our property is composed of 1 house type structure and 2 warehouse/metal shop buildings. The house was built in the early 1900s but is not used in our grow. The 2 warehouse buildings were built in 2005 & 2007 so should at least have newer pipes within them. I guess there could be a chance that the main line to the buildings could be old piping? But even if they were, wouldn’t you think that our R/O system would remove enough of the sediments? Let me know your thoughts and thanks again for your response.


That’s great news @oneofakindgenetics! Looking forward to seeing some pics and here’s hoping that things continue to improve. A big thank you to everyone who replied with their suggestions and help: @milessadowsky @shane @casey and @JoeGrow


Hey @oneofakindgenetics,

I saw that you had considered root rot, which is the direction I was coming from with that question. Not related to sediment filtration.

My only additional thought is that you might want to be going higher with pH rather than lower, depending on which chelating agent is used. You might also supplement that with a high quality fulvic acid for improved nutrient uptake.


We have seen a similar issue with our plants during their transistion from veg to bloom. Have you tried pulse watering, throughout the day? Coco is unique in that it can hold a ton of water but it doesn’t really become water logged as long as it isn’t sitting in it’s runoff, and there is still air pore space within the coco even when it is saturated.
We actually did experiments on watering our coco plants, frequent waterings vs waiting days between and the roots were still healthy and white on the plants that were watered even when the coco seemed completely saturated. Pulse watering allows for nutrients to pass thru the root zone more frequently --so more nutes are available to the roots more often. (like hydro) You can still get runoff and keep the EC/pH of the runoff in check this way. But runoff is key–even in veg, dont want the roots to sit in their own filth! (lol)

Also, not sure exactly what deficiencies you are seeing with the yellowing, but we have some strains that are pickier than others, and adding the product Cytoplus to our nutes a couple times a week has helped fix the yellowing we have seen for the most part.

Best of luck!!


Have you tried to just rinse the plants with a PH ballanced water inbetween watering? And what’s the temp of the water? Sometimes if the water is overy cold/hot from what the plant is use to that can shock the root system a bit causing yellowing if repeated every water. Room temp minus 10 to 15 degrees or so is where I like to keep things and I am hydro so similar to your medium.