DWC plant problems

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Akira90

Member
A55B3175-8437-4670-9CD5-6B1091DBCD81.jpeg A55B3175-8437-4670-9CD5-6B1091DBCD81.jpeg Hello everyone :)

I’ve been vegging for 4-5 weeks in DWC. The last week or so the plants started getting a little angry. Not all but over half of my babies.

*Running 400 or so ppm using jacks 3/2.2/ 1.5 Water is 10ppm starting out.

*pH set to between 5.6-6.4. Usually keep it around 6.1-6.3. Checked daily and it’s never gone lower the 5.6 but has gone as high as 6.9... (Edit).

*Roots look good, no bugs that I can see in the roots or leafs under a 60x

Water temp is 65-68 and there’s plenty of oxigination.

*Light source are cob led running 1000 micro moles /(uum/s). So for a veg cycle, way too high. I’ve turned them down to ~600, foliar fed with mag sulfate,

-Is this mag deficiency, too much light (1000+ uum/s which is 62.5 DLI...) poor VPD (for the last week or so my tent was pretty cold and running mid 70s and 55-60% as the humidity in the areas dropped like crazy. and my humidifier broke.

Foliar fed mag, lowered light uum/s to 600 from 1000, getting vpd in range. Anything would help. Thanks everyone!
 

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ConMer710

Member
Disclaimer: I am no expert just my personal experience.

How often do you check your ph? I was checking 1 time per day and my plants looked very similar to yours just much smaller. Transplant shock could have played a role in this but right when I started checking my ph 3 times per day the perked right back up.
 
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Akira90

Member
ConMer710 said:
Disclaimer: I am no expert just my personal experience.

How often do you check your ph? I was checking 1 time per day and my plants looked very similar to yours just much smaller. Transplant shock could have played a role in this but right when I started checking my ph 3 times per day the perked right back up.
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It’s checked daily if not twice a day. Usually between 6.1-6.3 but I started it out at 5.6 and it’s gone up as high as 6.9.
*I edited the top post to reply to this also
 
Hugo Phurst

Hugo Phurst

Well-Known Member
Try getting your ph closer to 6.
5.6 and (especially) 6.9 are too far off. Will cause lockouot.
Maybe bring your PPM up too.

Good luck
 
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ConMer710

Member
From my knowledge ideal ph for hydro is between 5.5 to 6.2. I would try to start your ph near 5.5 and let it get close to 6.2 but not over. Below if is a picture of when different nutrients can be absorbed by the roots. If you notice some of the nutrients cant be absorbed by the roots at 7.0 ph. When the ph is to high or low nutreint lockout occurs which is most likely what is causing your deficiencies
 

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CannaCountry

Well-Known Member
If you're using 1.5g of Epsom in your feed and you're spraying Mg via foliar, you're probably over doing it on the Mg, which isn't helping your situation. Also, pH is super important to manage; you'll need to close the gap between your lows and highs in terms of pH; as ConMer710 suggested, your pH may be locking out certain nutrients.

Your pics suggest an Mg issue, but with all the Mg you're putting into the equation, it would seem the Mg isn't available to the plant vs. it not being there to begin with. I'd research what locks out Mg and go from there.

In the meantime I'd double check my reservoir temps and be sure they're stable throughout the day. I'd also check the plant's roots...totally bright white roots are what you want. Anything less is suggesting an issue.

Just an observation; I too use Jacks, and a 3: 2 : 1: mix for me is near the upper range of pushing the plant. In other words, much more of a mix and I'll experience burning....seems your ppm of 400 is awfully low at that mix percentage. Are you sure of your ppm meter, can it be calibrated, can you test a known ppm to be sure it's working correctly?
 
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Akira90

Member
CannaCountry said:
If you're using 1.5g of Epsom in your feed and you're spraying Mg via foliar, you're probably over doing it on the Mg, which isn't helping your situation. Also, pH is super important to manage; you'll need to close the gap between your lows and highs in terms of pH; as ConMer710 suggested, your pH may be locking out certain nutrients.

Your pics suggest an Mg issue, but with all the Mg you're putting into the equation, it would seem the Mg isn't available to the plant vs. it not being there to begin with. I'd research what locks out Mg and go from there.

In the meantime I'd double check my reservoir temps and be sure they're stable throughout the day. I'd also check the plant's roots...totally bright white roots are what you want. Anything less is suggesting an issue.

Just an observation; I too use Jacks, and a 3: 2 : 1: mix for me is near the upper range of pushing the plant. In other words, much more of a mix and I'll experience burning....seems your ppm of 400 is awfully low at that mix percentage. Are you sure of your ppm meter, can it be calibrated, can you test a known ppm to be sure it's working correctly?
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I just foliar fed using mag the day before after thinking it was mag. The main reason I’ve upped the mag sulfate and cal nitrate in the ratio was to offset for my water being roughly 10ppm. Maybe I need to figure that out... I’ll look into this. Oddly I’d had assumed if anything I’d have a calcium lockout at these ratios but I’ve never seen deformed new leafs.

Both my ppm and ph meters have been calibrated and checked against a friends just to be safe.

My drift of that range has only happened once or twice over their life, mostly it’s been kept pretty stable around 6.1-6.3

Res has a chiller on it to be safe and I check the max / min on my little water probe meter and it’s ways +/- 2F

The 3/2.5/1.5 ratio if it were say gram/gallon on its own will have a much hottter mix but I’m using the ratio divided by the known PPM it produces vs the desired ppm. Then I weigh each part out and add mix it into my stock tank.

I’ve upped it to 580ppm using the 3/2/1 formula this time. I guess we’ll see.
 
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ConMer710

Member
Do you ever get your ph to 5.5? It is important to have the full range of ph between 5.5 and 6.2. If you look at that chart I posted mn can only be absorbed when the ph is below 6.

What I found works best for me is when I first wake up I set the ph to 5.5. By the end of the day it is between 6.0 and 6.2. I still check the ph midday but that cycle has been consistent.
 
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Akira90

Member
ConMer710 said:
Do you ever get your ph to 5.5? It is important to have the full range of ph between 5.5 and 6.2. If you look at that chart I posted mn can only be absorbed when the ph is below 6.

What I found works best for me is when I first wake up I set the ph to 5.5. By the end of the day it is between 6.0 and 6.2. I still check the ph midday but that cycle has been consistent.
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I’ll give that a try.
 
polishpollack

polishpollack

Well-Known Member
400 ppm, if I understand this thread right, isn't high enough for the high water content of DWC. Also, it seems like foliar feeding this plant tends to cause problems. 800 ppm might be much better.
 
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