SOIL Blotchy Discoloration of Leaves

[Trevret]

Hi guys, been away from this site for a couple weeks, hope you're all well! Woke up this morning to a fair number of discoloured leaves on my two plants; the smaller runt plant had the majority of them, however the bigger one had some too. Previously I was
advised on this site that I had a likely calcium deficiency, so I've been supplementing with Green Planet Pro Cal. I should also lnote I've been battling with acidic runoff since starting with Medi One, which is an organic fertilizer. It takes me FOREVER to get the feeding water up to an acceptable 6.5 before watering/feeding, however nonetheless I'm STILL getting runoff readings at 5 or so. Its important to note the OVERALL health of the plants looks great! We're talking clipping a few leaves here and there. But its adding up, and now this morning it's scary how many leaves were affected. Plesse note I fee yesterday. Any idea what's going on?

[Tersky]

It looks to me almost like a phosphorus deficiency but im betting its more to pH imbalance since it seems like that has been an issue for you. At least thats the closest thing i could find visually.

https://www.growweedeasy.com/cannabis-plant-problems/phosphorus-deficiency

[Trevret]

Thanks Tersky, looking at my babies this morning its becoming more apparent that the problem is likely ph. The one that has a correct ph has a healthy deep green color, while the other is yellowing; my question is what more can I do to correct the situation except what I'm already doing, which is making sure my notes read 6.5 before feeding. What else can I do?

[Tersky]

It seems to me that you are most likely growing in soil which i actually cant say I've ever done. I've done coco and hydro but never soil tho I'm thinking of doing it because it's ridiculous i haven't lol. Soil, especially organic, is something i cant really give solid advice about. I would have to defer to those with the experience. Maybe you could have nute lock and a good flush with plain ph water might help. Like i said tho, i am not experienced with it so take that with a grain of salt. I wish i could be of more help!

[Tersky]

bump. Soil growers?

[MeestaFeesha]

Ah, soil grower here! Not the best or most experienced, but I think I can chime in.

pH. Most the plants here have been fine with the wonderfully clean water we have (I can drive to the reservoir in 5min). However, Larry OG is a finicky girl...A side shoot that was super cropped has shown similar issues (photo attatched). I will admit here and hope no one sees...I've never pH'd, got one on the way to stop the ludicrousness.

Tersky you're a good person bumping the post! As well as with the Phosphorus link, I love GWE and the wealth of well written information!

[SoOrbudgal]

Got same issue on one branch, I never ph outdoors good well water and river irrigation. Call me OLD SCHOOL.

[Trevret]

Thanks for your help guys; I fed and tested my runoff yesterday, the ph SEEMS to be correcting itself, however I'm still seeing dramatic differences between the two plants. Take note that they're the same seeds, same soil, same pots, same everything. One is growing about 1/3 larger than the other, and has since birth. Yet it's the bigger one I'm having problems with now; its leaves are yellowing, and altogether lighter than the small plant, with variations of color as opposed to the rich, dark, uniformly deep green of the smaller plant. It's hard to accurately represent the problem in photos, as I'm using a phone, however if you look at the photos I've included here you can sorta see it; the bigger, problem plant is on the left; see the healthier colored plant on the right. I've used a flash as the Mars Hydro light is very yellow and distorts the color in photographs. An interesting thing to note (and my gut feeling of the source of the problem) is that the smaller plant dries out MUCH faster than the big one, thereby promoting a better feed cycle; I never know if I should feed or water the big guy, as the pot is always so much heavier with water weight than the little guy. So could it be a drainage issue? I potted them both identically... or could it just be the bigger guy (obviously) has a much bigger root system than the smaller one? I can tell you the buds on the bigger one are dense and huge, whereas on the little one are fluffy and arid...
Now, if it IS a drainage issue, what the heck can I do about it? These are auto flowers in full bloom .. I can't really repot it, can I? I also wonder if I just screwed up by using too-small pots? I picked 2 gallon pots, which I regret; my new babies are going into 3 gallon pots. Any ideas? Thanks again guys!