pH Lockout?

[ReikoX]

I'm on my second grow. Details can be found here.

2' x 3' x 4' cabinet
2 x 180 W Blackstar Chrome LED (110 W Actual)
4" ActiveAir 165 CFM inline fan
5 gallon fabric pots
Fox Farms Coco Loco organic soil
Biocanna Bio Vega
Biocanna Bio Flores
Canna Rhizotonic
Strain unknown bag seed.
Temperature 61-73*F
Humidity 30-59%RH
*pH in 8.0 - 8.2 out 6.8 - 7.4

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They look like a iron deficiency. The new growth is yellowing except for the veins. Bottom growth looks fine. I was under the impression that organic soil I didn't have to adjust it. That being said, a pH of 8.0 is 1000x a pH of 6.0.

* This measurement was taken over a month ago. Looks like I answered my question already

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The other day I tested my tap water pH and it read around 8. I thought it was out of calibration, so went to calibrate it. It read each solution correctly, so I got my trusty drops to measure again. The color matched close to 8.2, which also agreed with 8.1 reading of the pen. Run off measured from 6.8 - 7.4, so I'm not too stressed about it. I may need some pH down soon.

Unfortunately I convinced myself the issue was the lights and tried to supercrop my canopy. I may have been too heavy handed. So I plan to start to pH my water down to 6.0 and see if there is an improvement. Am I on the right track?

 

[exploziv]

sure looks like a Fe def. Iron is the first element that will lockout when ph is too high. Slowly lower the ph to desired level (around 6.5 should be the sweetspot for soil).
don't expect affected leaves to get better. check new growth and progression of the defficiency .. or lack of it for signs of plants getting Fe.

 

[ReikoX]

Thanks, that's what I thought. I watered with pH 6.0 water last night. I will wait to see if that keeps it from getting worse. Thanks

 

[Junky]

Best thing you can do is flush it alot like maybe a few gallons or more since its coco loco which if I remember correct has a good bit of perlite so you will be fine, then add a good bit of nutes in and check the pH of your runoff and if its too low then id flush some more until you see around 6.3pH, the runoff lets you see whats going on in the roots.

 

[ReikoX]

Thanks, I have been adjusting my pH to 6.0 and things have stabilized.