ExNavyInSTL
Active Member
Day 35 - Continued for Double Grape
Magnesium Deficiency
Likely Cause - Low pH in Coco
I noticed late last night that one of the leaves on Double Grape was showing early signs of a Magnesium Deficiency.
Off to Google I went, because I can never remember deficiency photos (except calcium - most of the time).
The first thing up was an article from Sensi Seeds: (Click Here: Magnesium deficiency in cannabis plants)
My gut tells me my issue is not a lack of Mg in the soil, but excessively low pH.
Here's Why:
pH in 12-gallon Reservoir stays consistently around 6.2 (ish). Below are the readings for the last 5 days in the Rez.
pH in the AquaValve Reservoir for the last 5 days:
What my Excel Chart Leaves out is that yesterday it was 4.39 pH at the AVC. I corrected it to 6.00 and this morning it was 5.19 pH
Question: What Nutrients (or supplements) are known for bringing pH down?
I know Silica supplements "can" bring down pH, but I don't use Potassium Silicate for my Silica. I use mono (ortho) silicic acid and it has never pulled pH down like this.
Could it be one of the N-P-K or minors doing this?
Thoughts: I do add supplements such as Recharge (twice), and Ca/Mg (once) as a drench, but I always pH them to the low 6's (6.10 - 6.20). Then once the fluids drain throughto the AVC, I remove the fluid from the AVC and lower its E.C. (which was raised from passing through the Grow Dot infused Coco), and I restable the pH. Within a day or so, I remove the fluid again and go back to very low E.C. Rez Water that is about 6.20 pH.
I know things like this happen in a grow, but I would like to be better about knowing why?
What I have Done So Far:
I have Microgenics 0.75 as my go-to foliar for most common situations. So, I localized the treatment by spraying my fingers and massaging it in to the affected leaf. I gave both plants a little spritz, but I made sure to treat the leaf to see if it can draw up into the leaf.
Click Here to Learn more about: MicroGenics 0.75
What I Plan to Do:
Run some RO Water through and collect the run-off from the AVC. I'll check EC and pH, then lower E.C. to about 1.5 and pH to about 6.2 (if needed).
I don't have a Soil pH attachment for my Apera Pen, so I'll depend on the run off water for now.
Magnesium Deficiency
Likely Cause - Low pH in Coco
I noticed late last night that one of the leaves on Double Grape was showing early signs of a Magnesium Deficiency.
Off to Google I went, because I can never remember deficiency photos (except calcium - most of the time).
The first thing up was an article from Sensi Seeds: (Click Here: Magnesium deficiency in cannabis plants)
My gut tells me my issue is not a lack of Mg in the soil, but excessively low pH.
Here's Why:
pH in 12-gallon Reservoir stays consistently around 6.2 (ish). Below are the readings for the last 5 days in the Rez.
12 gal Rez: 6.16; 6.24; 6.23; 6.20; 6.20 (Average: 6.21) |
pH in the AquaValve Reservoir for the last 5 days:
AquaValve Compartment (AVC): 5.56; 5.73; 5.56; 6.00; 5.19 (Average: 5.61) |
What my Excel Chart Leaves out is that yesterday it was 4.39 pH at the AVC. I corrected it to 6.00 and this morning it was 5.19 pH
Question: What Nutrients (or supplements) are known for bringing pH down?
I know Silica supplements "can" bring down pH, but I don't use Potassium Silicate for my Silica. I use mono (ortho) silicic acid and it has never pulled pH down like this.
Could it be one of the N-P-K or minors doing this?
Thoughts: I do add supplements such as Recharge (twice), and Ca/Mg (once) as a drench, but I always pH them to the low 6's (6.10 - 6.20). Then once the fluids drain throughto the AVC, I remove the fluid from the AVC and lower its E.C. (which was raised from passing through the Grow Dot infused Coco), and I restable the pH. Within a day or so, I remove the fluid again and go back to very low E.C. Rez Water that is about 6.20 pH.
I know things like this happen in a grow, but I would like to be better about knowing why?
What I have Done So Far:
I have Microgenics 0.75 as my go-to foliar for most common situations. So, I localized the treatment by spraying my fingers and massaging it in to the affected leaf. I gave both plants a little spritz, but I made sure to treat the leaf to see if it can draw up into the leaf.
Click Here to Learn more about: MicroGenics 0.75
What I Plan to Do:
Run some RO Water through and collect the run-off from the AVC. I'll check EC and pH, then lower E.C. to about 1.5 and pH to about 6.2 (if needed).
I don't have a Soil pH attachment for my Apera Pen, so I'll depend on the run off water for now.