Please help me diagnose an issue in my DWC system

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TheOhmOne

TheOhmOne

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I’ll cut straight too it. Thank you for stopping by.

Setup:

1) Growers Choice ROI720 LED @30k Lux currently (75%)

2) 150L insulated res. Holds 35 gallons of solution

3) Sour D clones

4) 6” net pots

5) 400 cfm filter and fan exhausting

6) 12k btu ducted in

7) 5x5 tent

8) 4x5 scrog net

9) 165L/min of air being pumped with air stones and air discs

10) BlueLab Guardian PH/PPM,Temp for Res

11) TrolMaster HydroX climate controller, Temp, Humidity, PPMs, VDP with App

12) TrolMaster AquaX PH probe, Temp and PPM probe with App

13) 3 x clip-on air fans

14) 2 gallon humidifier

There is No Co2 being added. I just take the reading to track what the natural occurring levels are in my tent over time.


Nutrients:

1) 7 stage RO water. Final step is UV treatment

2) H&G Aqua Flakes A&B 50/50 ratio

3) Botanicare Hydroguard

4) Botanicare Cal-mag

5) GH PH up&down


The Numbers:
Climate:
Temps: 70-80f according to the TrolMaster I have about 7 degree fluctuations in 10 minutes periods, or the sensor is overall sensitive and it’s catching drafts, ext... idk if this is an issue or not, idk how I have 10 degree temp swings ever.... my lights are on 24/7...... never been off.

Humidity currently 55-70%. See below

NaturalCo2 PPMs: 500-1000. Avg around 500

Res Solution
63-66F

PH: 5.8-6.2

PPMs: Have dropped by around 40-80 PPMs every single day throughout all 5 weeks of veg for the most part.
I’ve started at 200 and each week changed the Res, and increased by 200 up to now 1000 PPMs.

Well it’s 1000PPMs for BlueLab and 600 and change for TrolMaster.

So it depends what scale you use.

I Cannot get the PH to stay below 5.8. I will lower it to 5.6-5.7 and it will rise to 5.8-6.0 within 24 hours.

The PH always drops in conjunction with this. Usually about 40 PPMs on average per 24 hours. However sometimes more. For instance.
This last increase from 900 to 1000 and the plants took it back down to 900 in 24 hours and drank about 6 gallons of water. Shits crazy.

You can see the light/bright new growth. I knowlighter new growth is normal. But this seems excessive.The plant is growing like crazy through so maybe it just can’t keep up with new growth ?

Maybe over fert and locking out? Can someone explain the PPM drop then ? I would like to be corrected if the PH rising, PPM dropping, and water level decreasing is not an indication the plant is taking in more nutrients then water. Therefore, increase feed ?

I had low humidity for the first 3-4 weeks.20-30%. Could this have caused issuespushing the start of week 6 still ? My humidity has been steady at 55-70 for about 2 weeks. A majority of my concerns are new growth. My though is, the low humidity messed with transpiration rates and therefore effected nutrient uptake?
I’ve done 2 Res changes since increasing humidity. The 3rd will be done today.

Another thought I had... maybe I am training them too hard and trimming too much ? They are growing so quick I have to be very very aggressive. The continue to grow at a crazyrate though so I’m not so sure they don’t like it??



Please help me figure out this light/ bright new growth, rising PH , and dropping PPM. I appreciate
 
Please help me diagnose an issue in my dwc system
Please help me diagnose an issue in my dwc system 2
Please help me diagnose an issue in my dwc system 3
Please help me diagnose an issue in my dwc system 4
Please help me diagnose an issue in my dwc system 5
Please help me diagnose an issue in my dwc system 6
Please help me diagnose an issue in my dwc system 7
Please help me diagnose an issue in my dwc system 8
Please help me diagnose an issue in my dwc system 9
Please help me diagnose an issue in my dwc system 10
Please help me diagnose an issue in my dwc system 11
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TheBioMaster

TheBioMaster

450
93
Drop the cal/mag.....its not needed with Aqua Flakes at all.

The PPM drop is a good thing..sorta..Lol!!

To correct...you need a "top off tank" with the PPM's slightly higher than what the system is at.

If the system is at 1000ppm, try 1200ppm in the top off tank.

That will keep PPM at 1000 or whatever your running at.

You will need to tweak the PPM in the top off tank until your PPM's stay steady in the system.

What week are you in??

They look fine. Dropping cal/mag will help to lower and stabalize PH......uptake of nitrogen will increase. Its normal for new growth to come out yellow and then green up over time. Its because of the fast growth.

Adding drip clean would help.

Excellent information and grow!!
 
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TheBioMaster

TheBioMaster

450
93
Forgot to mention that the top off tank will also keep water levels steady in the system.

Those big fat round roots busting out of net pot is from the water level dropping to low below the net pot. Not really a problem though. But when water levels stay steady and high enough, you get a nice spaghetti root mass.......long stringy thin roots.

Not a biggie though....shouldn't hinder your harvest at all.
 
TheOhmOne

TheOhmOne

147
43
The BioMaster! Thanx for providing your info.

Sadly there is no top off Res in this system. About 35 total gallons, getting topped off with 5 gallons per day, usually adding nutes to that 5 gallons upon top offto bring up ppm to counter daily ppm drop.

I didn’t think I needed the Cal-mag with Aqua flakes so the first few weeks it was a very light feeding. I’ve since increased my Cal-mag ratios in and effort to counteract the lightcolored new growth and occasional discolored leaf.

I’m currently on day 43 of Veg from first root out of the rockwool clone.

My concern is becoming the lighter growth appears to a little lighter/brighter toward the inner leaf, and when aging, these leads are sometimes not taking on good color ext, I just want to make sure these ladies are 100% before flipping to flower

Thank you again for the response

Drop the cal/mag.....its not needed with Aqua Flakes at all.

The PPM drop is a good thing..sorta..Lol!!

To correct...you need a "top off tank" with the PPM's slightly higher than what the system is at.

If the system is at 1000ppm, try 1200ppm in the top off tank.

That will keep PPM at 1000 or whatever your running at.

You will need to tweak the PPM in the top off tank until your PPM's stay steady in the system.

What week are you in??

They look fine. Dropping cal/mag will help to lower and stabalize PH......uptake of nitrogen will increase. Its normal for new growth to come out yellow and then green up over time. Its because of the fast growth.

Adding drip clean would help.

Excellent information and grow!!
 
TheOhmOne

TheOhmOne

147
43
Yes currently I can’t control this, that’s what only 24 hours of drinking is doing. I got plenty of Res/root space though so I am not worried if the first few inches are chunky supports. I will look to fix this in the future with the suggested top off tank.

Pics coming soon of the current roots when I do a res change here shortly. These things are INSANE. The roots have grow so much in this 150L cooler that they have begun pushing the netpots up out of the lid.

Any advice on when to flip these SourDs?

Should I add another screen to better fill canopy.? I have some pretty high spots that I don’t think I will be able to print down to net level anymore. I’ve tried tying them down and being very aggressive. But still not luck. The left one essentiallygot supper cropped about a week ago when the top 6” of the main stem broke when I was trying to bend under net. This actually helped keep the canopy more even-on the left plant.

Oh one last thing for now... do you see any issues with them being in same Res? I’ve ran these before and no issues, but maybe I got lucky. Any change the root masses are fighting for nutrients?

thanx again!!

Forgot to mention that the top off tank will also keep water levels steady in the system.

Those big fat round roots busting out of net pot is from the water level dropping to low below the net pot. Not really a problem though. But when water levels stay steady and high enough, you get a nice spaghetti root mass.......long stringy thin roots.

Not a biggie though....shouldn't hinder your harvest at all.
 
TheOhmOne

TheOhmOne

147
43
Here is the Climate

The Res data currently, and The Res data from 1.5 days ago when topping off. It’s now been, 36 hours between these pics, I will be changing Res here shortly.

Should I be increasing or decreasing ppms? I would say increase, but curious everyone’s thoughts. Also when people recommend a ppm what scale is that? .5 or .7 ? This big difference

Thank you everyone
 
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TheBioMaster

TheBioMaster

450
93
Holy cow! I thought you were already in flower. You should flip.

I've never vegg'd a rooted clone for more than 2 weeks......in RDWC its just not needed.

I keep forgetting your in DWC and not RDWC.

As far as EC goes, you use .5 if your in the USA and .7 if your in Europe.

You'll fill that net by week 3 of flower. And a 2nd net and maybe even a 3rd net would be good.

The good news is that in flower, simulating a drought by lowering water levels is suggested to improve growth. But this is done in late stages of flower..... Like after week 6-7.

Try and keep the water levels steady and no more than a inch down from bottom of the net pot. PPM drops are expected in DWC. When the plants eat/drink they release ions into the water that changes the PH....so PH instability is expected. All signs the plants are healthy and your nutrient mix is not to hot.....

The yellowing is expected due to your PPM drops.....its all related and tied together.

RDWC has advantages over these problems.......

Best thing you can do for now is get a 35 to 40 gallon top off tank and two 5$ float valves to control the water levels.
 
TheOhmOne

TheOhmOne

147
43
ahh! I was just wondering that. That makes a lot more sense. I feel like that needs to be clarified more frequently online and .5 or .7 ppms are very different.

is 1000 ppms excessive pre bloom ? Should I fill to 1200 ppms this res change? Do you think the 50/50ratios of Aqua A&B is enough?
Should I supplement with a little cal-mag?
I also have some DynaGro Pro Tek, should I add this in now?

I’ve always read that Sour D was a picky strain. So maybe that’s just these genetics?

I was to ensure I am done stressing them before I flip for the most part. The thing is I don’t think if I flip right now, that I’ve maximized my space.

I think my fault here was the scrog sceeen being too low and method of training used being too late/friendly in the beginning. Clones are a a pain in the ass when you don’t take them yourself. I feel like I started training as soon as they looked rooted fully and stable in the main res.

My plan now was to place another new about6” above the 1st net and use this to spread thecanopy to the missing areas. I would them lollipopunder both screen, flip the lights, and then tuck for another around 1” days or so depending on stretch. Then let them grow up after about 10days to 2 weeks.

so the ideabehind the 2nd screen isn’t to create 2 canopy’s or something, outs because the first screen has allowed some branches to become to thick and long past the screen. Therefore making thecanopy uneven, and scrog useless for majority of theback side.

2nd screen would allow my to push/tuck the high shoots down enough to allow more lower shoots to even out.What y’all think ?



Holy cow! I thought you were already in flower. You should flip.

I've never vegg'd a rooted clone for more than 2 weeks......in RDWC its just not needed.

I keep forgetting your in DWC and not RDWC.

As far as EC goes, you use .5 if your in the USA and .7 if your in Europe.

You'll fill that net by week 3 of flower. And a 2nd net and maybe even a 3rd net would be good.

The good news is that in flower, simulating a drought by lowering water levels is suggested to improve growth. But this is done in late stages of flower..... Like after week 6-7.

Try and keep the water levels steady and no more than a inch down from bottom of the net pot. PPM drops are expected in DWC. When the plants eat/drink they release ions into the water that changes the PH....so PH instability is expected. All signs the plants are healthy and your nutrient mix is not to hot.....

The yellowing is expected due to your PPM drops.....its all related and tied together.

RDWC has advantages over these problems.......

Best thing you can do for now is get a 35 to 40 gallon top off tank and two 5$ float valves to control the water levels.
 
TheBioMaster

TheBioMaster

450
93
Call me crazy ......but I think those plants are going to double to triple in size during first 3 weeks of flower and you will run out of space. Container will become root bound......The yellowing will get worse and spread as roots fight for water and nutrients......your already seeing signs of it IMHO.

DWC growth rates are undeniable.....

I started in DWC about 25 years ago before moving on to RDWC after about 5 years.....can't count how many times I over grew the space vegging to long......your harvest and quality suffers from lack of space. The top of the plant can run out of space just like the bottom of the plant can.....and both hinder final outcome.

Cannabis doubles and sometimes can even grow 4x in size during the first 3 to 4 weeks of flower. You don't have the space for that currently.

The 2nd and 3rd net suggestion was strictly for support for when you over grow your space.
 
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TheOhmOne

TheOhmOne

147
43
Call me crazy ......but I think those plants are going to double to triple in size during first 3 weeks of flower and you will run out of space. Container will become root bound......The yellowing will get worse and spread as roots fight for water and nutrients......your already seeing signs of it IMHO.

DWC growth rates are undeniable.....

I started in DWC about 25 years ago before moving on to RDWC after about 5 years.....can't count how many times I over grew the space vegging to long......your harvest and quality suffers from lack of space. The top of the plant can run out of space just like the bottom of the plant can.....and both hinder final outcome.

Cannabis doubles and sometimes can even grow 4x in size during the first 3 to 4 weeks of flower. You don't have the space for that currently.

The 2nd and 3rd net suggestion was strictly for support for when you over grow your space.

I 100-% understand as I have experienced this before. However I think this one is only slightly over grown if any. I think it will still be fully manageable unless this strain is just absolutely crazy in the first few weeks.

with the added screen above I’m confident I can smash these down and trim up enough that the top of my canopy will be filled with very thick branches..
Only down side here is the added 6” of starting canopy height, and also higher risk of PM with so many Colas going to be bunched together.
I’m counting on the fact my average RH is 20-30% with no humidifier added. I also have a dehumidifier for flower so I’m confident I can keep humidity in check.

I then plan on using Yo-Yos to not only support, but guide the colas away from each other and into particular locations, I do this pretty gently compared to my vegetative training,

What issues do you see with this? I’m not saying I’m right, just sharing what my plan was and what I have done in the past. However I know this can be really strain dependent at this point.

I will flip the lights today. If I just changed the Res, do I need to do anything else with these Aqua Flakes? I’ve never ran them, or is it 50/50 throughout till harvest ?

Thank you again
 
TheOhmOne

TheOhmOne

147
43
Res change complete.

Funny Story.....

I went to calibrate my ph and ppm probes like I do every week.... I attempt to pull them up... won’t budge... what gives ??

The roots have completely encapsulated the probes. There is absolutely no why I could get them out unless I removed a large chunk of roots. Hopefully they continue to have similar reading to each other. I am glad I have the redundancy now.

It’s crazy that in just over A week though it completely ate those probes lol.

Anyways.

I cut the Cal-mag.

Only Aqua A&B
and Hydroguard in the Res now.

At 1170PPMs
5.8PH
64F

I am going to build out the 2nd screen today. Then flip the lights to 12/12.

any suggestions before switching to flower?

thank you all!!!
 
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TheOhmOne

TheOhmOne

147
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Here some pictures of the leaf temperatures at high points and low points in the canopy

Also Lux readings at those locations as well.
 
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TheOhmOne

TheOhmOne

147
43
Here photos of the 2nd net that was added today to help even out the canopy.

I also turned off the light today to officially start 12/12

I am going to let them grow up to the 2nd screen and train for up to 2 more weeks.

The root masses are beginning to significantly push the netpots out of the Res. I will need to figure something out to keep these down as they are pushing up pretty high. The tape isn’t working at all.

Do people recommend running Aqua flakes A&B 50/50 throughout all of bloom?

My climate is actually steadier with AC and Light off so far.
 
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TheOhmOne

TheOhmOne

147
43
I still honestly feel like something isn’t 100% right here with the new growth.

its too bright/light.

I’m afraid this may be lockout from over feeding them. Can they still be eating up to 100 ppms a day if they are over fed? If a particular element becomes locked out, will the plant continue to uptake larger amount of nutrients trying to fill the deficiency? Or when over feeding in DWC does the PPM always rise ??

The bright growth is very distinct. The older growth is even inconsistent. Almost tie-die looking leaves from light and dark shades of green.

Should I stop the H&G? This is my first time running it and I didn’t really realize they recommend running only A&B at 50/50 ratio until harvest. That seems crazy in almost 2021 to keep your bloom and veg ratios the same for Cannabis.........

Someone please chime in, I got a lot invested here.
 
TheOhmOne

TheOhmOne

147
43
Once again my main concerns are as follows:

  1. Light/bright mew growth
  2. Tie-die looking older growth
  3. Temperature fluctuations when lights are on? I have up to 10f fluctuations with lights on. I’m thinking of adding another exhaust fan and filter to get better air flow? I currently only have 400cfm and a 12k btu portable ac. So I may néed more exhaust?
  4. Recommend PPM based of my past data. Previous experience with Sour D Strain. Or experience with Aqua Flakes. I’m at 1200 ppms currently, or 750 depending which scale. And this is the highest I’ve ever ran. Normally I’ll barley push 1200 at the end of flower....
  5. Any tips on how to get my portable ac to work off a timer or controller? I’m not sure it turns back on automatically after it’s shut off. Has anyone found a work around for this?
 
TheOhmOne

TheOhmOne

147
43
So.... updates after the first night of darkness....

I ran into a few issues that I will have to handle ASAP.

1st issue: LED didn’t wanna turn off via the light controller once commanded

2nd issue: 1 minute after the light turned off(manually) the temp jumped to 68f instantly. I turned the AC off and the temp held steady at 74-76 all night long

3rd issues:Humidity got a little high with the tent closed all the way. I opened up the doors for now and it kept the humidity at 65% steady all night. However I can’t leave tent open once buds appear, as these are already reeking Up the whole house.

4th issue: Portable ac unit timing. I’ve sort of got this one figured out now. I called LG and I can install my own external thermostat on the unit and take temp reading from anywhere I want. Instead of the unit. (The unit is not in the tent, it’s only vented in) I also was concerned about turning the unit on and off, and it automatically restarting. Well it turns out this unit will automatically power back on in the event of a power failure, this makes things very easy as any old timer will work now. I will still be using Trolmasters device timer though so that I have the ability to turn anything on or off form my phone. (Light, AC, Fans, ext.)

PH and PPMs are finally steady for 24hours!!
Holding at 1250 and 5.7 PH currently.

Should my light intensity be at 100% now that I’ve switched to 12/12?
 
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