PPM question for advanced growers

[Luketheduke]

First off thanks for what yall do guys.

So im trying to understand the ppm readings for runoff, and slurry tests associated w feeds.

(Trying to tell if its too much nutes or not enough, plant had nute burn early on)


So SG18 (week 2 flower) slurry test had a PH of 6.9 w PPM of 171. I still need to collect runoff for this one.

This is my main concern here. G18-2 getting fed every other day. Feed is tiger bloom at 1/2 dose. PPM 471. PH. 6.5. For the run off thr PH is 5.92 and PPM is 247. Slurry test put.PH at 7.2 and ppm at 294.

So judging by the numbers for G18-2. She needs to be fed right? Pics of G18-2 attached.

For more info please visit in depth grow journal on this sites grow journal section.

 

[low_and_slow]

slurry test had a PH of 6.9 w PPM of 171. I still need to collect runoff for this one.

Feed is tiger bloom at 1/2 dose. PPM 471. PH. 6.5. For the run off thr PH is 5.92 and PPM is 247. Slurry test put.PH at 7.2 and ppm at 294.

Something doesn't sound right here.

The slurry test sounds okay in the first part of your post, a little high for my taste, but 6.9 won't kill a plant. Then you say you do another slurry test and get a pH of 7.2 at 294 ppm, which is definitely too-high and would cause lockout potentially, but nothing that would be like an emergency.

But if you're feeding at 6.5 and getting 5.92 out, that doesn't really align with what your slurry tests are showing. Something in the root zone is dropping the pH of your feed down over 1/2 a point, which is a big change given that the pH scale is logarithmic (meaning that each decimal of pH change is like 10x the acidity).

Your pics look like phosphorous deficiency, but I'd actually guess phosphorous lockout due to pH.

Can you confirm your numbers and maybe just re-explain a little bit exactly what you're seeing?

 

[Luketheduke]

Something doesn't sound right here.

The slurry test sounds okay in the first part of your post, a little high for my taste, but 6.9 won't kill a plant. Then you say you do another slurry test and get a pH of 7.2 at 294 ppm, which is definitely too-high and would cause lockout potentially, but nothing that would be like an emergency.

But if you're feeding at 6.5 and getting 5.92 out, that doesn't really align with what your slurry tests are showing. Something in the root zone is dropping the pH of your feed down over 1/2 a point, which is a big change given that the pH scale is logarithmic (meaning that each decimal of pH change is like 10x the acidity).

Your pics look like phosphorous deficiency, but I'd actually guess phosphorous lockout due to pH.

Can you confirm your numbers and maybe just re-explain a little bit exactly what you're seeing?

Yeah the slurry test I did yesterday (five days after the first one) was a bit high. But not too alarming. Something I can drop with. Few low ph waterings.... So should I continue to feed every day and drop the PH of the feed or should I stop the feeds and use plain water thats ph'd down a bit until the soil ot back in range?

Because if its going in at 471 and coming out at 247 then its getting some nutes right?

 

[Mañ'O'Green]

What are you growing in? Using run-off information is not reliable. The roots can and will change the PH in the root biome by exuding substances that change the PH. This is done to signal the microbes to produce the nutrients to plant is wanting. When you shift your input PH to accommodate what is coming out the bottom you are messing with what the plant wants. Always PH your input to the substrate's optimal range. Do not use run-off in this manor. I do not use it at all.

Your nutrient input is out of balance and lock-outs are predictable.

Tutorial - A word on Nutrients

The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...

www.autoflower.org

 

[Luketheduke]

What are you growing in? Using run-off information is not reliable. The roots can and will change the PH in the root biome by exuding substances that change the PH. This is done to signal the microbes to produce the nutrients to plant is wanting. When you shift your input PH to accommodate what is coming out the bottom you are messing with what the plant wants. Always PH your input to the substrate's optimal range. Do not use run-off in this manor. I do not use it at all.

Your nutrient input is out of balance and lock-outs are predictable.

Tutorial - A word on Nutrients

The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...

www.autoflower.org

Were talking about PPM with the runoff. I do slurry tests for my results. All other measurements are for reference only.
Ill keep my watering and feeds at the normal.level lie you said and not use it to adjust the soil ph. Ill order soil acidifier and garden lime to tackle that issue


Ultimately what I need to know is If im feeding at 470 approx. And it comes out at 270 approx. Does that mean that its eating?

 

[Mañ'O'Green]

Were talking about PPM with the runoff. I do slurry tests for my results. All other measurements are for reference only.
Ill keep my watering and feeds at the normal.level lie you said and not use it to adjust the soil ph. Ill order soil acidifier and garden lime to tackle that issue


Ultimately what I need to know is If im feeding at 470 approx. And it comes out at 270 approx. Does that mean that its eating?

Yes, No, Maybe? What are you growing in?

Lime adds alkaline not acid. If you are in soil this should have been added months before starting the grow?

Edit: Oops missed the and - Ill order soil acidifier and garden lime

 

[Mañ'O'Green]

I need to get the whole picture of what you are doing. Please be detailed about your grow medium.

Please fill in this form: (copy and paste part is below, this first one tell what specifically to include)

-Problem: (brief description)
-Medium/grow method: soil; soilless-- coco, or peat based like Promix, etc. (please provide the actual product name); DWC, NFT, etc.
-Feed and supplements used: include brand, dosage/strength, frequency of feeding and watering (alone); method-- by hand, drippers, rercirc' or drain-to-waste,... N-P-K #'s too if you can!
-Water source: RO/DI; tap- dechlorinated-?..... EC or TDS reading; pH (don't bother with this on RO/DI, do bother with TDS/EC though to confirm it's working well enough)
-Strain and age
-Climate: night and day ambient T and RH%; res' temperatures; any extremes in T/RH% exposure
- Light used: HID, LED, COB, combo of,... wattage; light cycle hours (20/4, 18/6 , etc.); distance to tops....
-Additional info: PH in the root zone. How long have the plants been affected?...How fast did symptoms appear?... Anything else you think might be relevant..

--Pictures including WHOLE PLANT PICS, and troubled leaves.. use normal light or flash as other light sources ruin color rendering, critical for diagnostics! Turn off the grow lights.

✂ - - - - - - - - - - -
(copy and paste)-->

Problem:

Medium/grow method:

Feed: and supplements used:

water source:

PH in the root zone:

Strain/age:

light used:

Climate:

Additional info:

 

[Luketheduke]

Yes, No, Maybe? What are you growing in?

Lime adds alkaline not acid. If you are in soil this should have been added months before starting the grow?

Lol im getting the lime to have in my arsenal. If you have PH down you should also have PH up, that kind of thing. The Soil Acidifier would be used for the acid adjustments.

 

[Luketheduke]

I need to get the whole picture of what you are doing. Please be detailed about your grow medium.

Please fill in this form: (copy and paste part is below, this first one tell what specifically to include)

-Problem: (brief description)
-Medium/grow method: soil; soilless-- coco, or peat based like Promix, etc. (please provide the actual product name); DWC, NFT, etc.
-Feed and supplements used: include brand, dosage/strength, frequency of feeding and watering (alone); method-- by hand, drippers, rercirc' or drain-to-waste,... N-P-K #'s too if you can!
-Water source: RO/DI; tap- dechlorinated-?..... EC or TDS reading; pH (don't bother with this on RO/DI, do bother with TDS/EC though to confirm it's working well enough)
-Strain and age
-Climate: night and day ambient T and RH%; res' temperatures; any extremes in T/RH% exposure
- Light used: HID, LED, COB, combo of,... wattage; light cycle hours (20/4, 18/6 , etc.); distance to tops....
-Additional info: PH in the root zone. How long have the plants been affected?...How fast did symptoms appear?... Anything else you think might be relevant..

--Pictures including WHOLE PLANT PICS, and troubled leaves.. use normal light or flash as other light sources ruin color rendering, critical for diagnostics! Turn off the grow lights.

✂ - - - - - - - - - - -
(copy and paste)-->

Problem:

Medium/grow method:

Feed: and supplements used:

water source:

PH in the root zone:

Strain/age:

light used:

Climate:

Additional info:

Im just trying to figure out how to use the PPM numbers to know when to feed. Because nothing Ive read clearly states an answer.

 

[Mañ'O'Green]

Im just trying to figure out how to use the PPM numbers to know when to feed. Because nothing Ive read clearly states an answer.

That is because there is no clear answer. Every seed will grow a different plant and every different plant will have different needs. I cannot help much if you dont want to answer my questions.