Problems with newest grow (Yellowing and browning)

Im at day 70 something of a bag seed grow. Started with 9, 1 was male, i now have 8 left in their 4th week 2nd day of Flower. Im using fox farm nutes (the big 3 + Cal mag as of 2 waters ago), full organic soil medium, and 3 130w high efficiency LED Grow lights. If you need more info, please let me know. The problem im having is a few weeks ago, i started noticing light brown spots on lower and mid leaves. After a few days the leaves would shrivel, brown, and fall off dead. I did a full flush with just water 6 days ( 2 waters) ago; Slight improvement but still happening. Upon further investigation, i found out that my soil pH is in the 7.5-8 range and has been since i first planted these suckers. I figured it would go away with nutes and pHed water but apparently, it hasn't. I know it could be the pH and that the soil can't soak up the nutes, but i need an experienced grower who can really break this down with me.

This is the chart i am using, only the first 3 nutes, though. Big Bloom, Grow Big, and Tiger Bloom (+ the Cal-Mag Fox Farm previously mentioned @2tsp pers 2Gal)

Looks like you might have some lockouts from ph or abundance of nutrients. Fox farms can be very strong are you using it at full doses?

What soil
Temp/humidity
Size of pots
Feeding and watering schedules and strengths.
mare you checking ppm or ph?

I will post a picture of the different soils that I used. I mixed most of what's in the picture together in equal parts with a couple variations. Temperature and humidity levels typically range between 65 and 75° and the humidity ranges anywhere from 50 to 65%. If it gets up to 65 I vent the room properly to get it back down to the 50% range. They are 3 gallon pots. And the feeding and watering schedules should be on the chart that I posted from Fox farm; I use 2 gallons of water so I double everything on the chart. Typically I'll go three to four days between watering, using the knuckle in soil method to tell if they're dry yet. I AM using full amounts of recommended nutrients from the schedule, I just read somewhere else that isn't great sometimes lol I had no idea, this is only my 4th grow. This is the first time I've ever used Fox farm EVER; every grow before this has been 100% natural with the exception of a little molasses in the water at the end of the grow to thicken and sweeten the buds.


I didn't use the Miracle-Gro seed starter though just everything else.

Another thing to mention is I'm not sure why but like mentioned before the pH of my soil has been around 7 to 8 since I planted them. Even my water from the tap and filtered water are both around 7 to 8 pH. I'm way too far in the grow to add something to the soil unless it's like to the top layer when I water it. I saw vinegar and lemon juice added to it could be helpful but then I also saw that it doesn't have something in it that will help keep the pH down but will only be temporary. I've got about 3 weeks left before I chop them. I think off the top of my head my chop and dry day is October 21st

You're in your 3rd week of flower and you got about 3 weeks left? What strain are you able to turn around that quick?

I would try to keep the ph of your nutrient solution a little on the lower side, maybe 6.0? Your tap water might contain high amounts of buffering elements causing your ph to rise and making it very difficult to come back down, either way cannabis plants will handle a lot! Although it’s PH might not be in its ideal zone it will still continue to grow but I would slowly make small corrections. Don’t shock the plant by dropping its ph in a matter of an hour.

I don’t see anything to alarming with your plant, it could be PH if you really are reading over 7. It could also be salt build up.
also I would let them flower for at least another 5 weeks.

MannyPacs said:

You're in your 3rd week of flower and you got about 3 weeks left? What strain are you able to turn around that quick?

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Bad math. Its early and im stoned hahaha

I think you may be right @keep it real. I did a test of my tsp water by adding lemon juice until it dropped to 6.0 Initially it read 8 and after almost a QUATER CUP, not just the recommended couple drops, in a cup of water mind you, it dropped to 7. So is the slowed growth ok? just flower for longer to compensate and how can i balance my ph of the solution, any recommended additives? Sorry for the 20 questions, i want to soak up as much info as i can.

LukeSkybud said:

Bad math. Its early and im stoned hahaha

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I wasn't even on no bull I was really wanting to know what strain you had found if it was that quick lol. I personally always had trouble mixing peat with coco. My taps almost 8 as well and hard as a rock but don't need no calmag that's for sure lol I do Need to use the more concentrated phosphoric acid to bring it down. Slowish Flush with half strength nutes ph at 5.6-5.8. good luck

I've actually got a detailed journal of all the dates an amounts of nutrients used since flower if that would help. Switch to 12:12 was 8/23

MannyPacs said:

I wasn't even on no bull I was really wanting to know what strain you had found if it was that quick lol. I personally always had trouble mixing peat with coco. My taps almost 8 as well and hard as a rock but don't need no calmag that's for sure lol I do Need to use the more concentrated phosphoric acid to bring it down. Slowish Flush with half strength nutes ph at 5.6-5.8. good luck

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It's all bag seeds. Random seeds that I've saved in a jar in my freezer over the last couple years. I got the Cal mag because I thought there was a deficiency but after talking to you guys I'm starting to think the whole pH might be the issue. So the concentrated phosphoric acid, is that something I can get on Amazon?

Like manny said, I would just try to get filtered water that’s not as hard and use half dose nutrients. My water here is hard as hell too!!

The last eight are from a couple minutes ago. All the rest are from the last 1-4 weeks

LukeSkybud said:

I've actually got a detailed journal of all the dates an amounts of nutrients used since flower if that would help. Switch to 12:12 was 8/23

View attachment 5203033

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Good notes man! Insane you had that many females out of bag seed lol.
mine thing I notice is it says cal mag, I would t cal,mag with your water being so Hard.

So all of my water in the house goes through a whole house filter even my fridge has its own filter. All of that still at 8pH, so is there anything that I can add to the water to lower it or is my best bet just buying gallons of distilled water

keep it real. said:

Good notes man! Insane you had that many females out of bag seed lol.
mine thing I notice is it says cal mag, I would t cal,mag with your water being so Hard.

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Thanks! After my first few grows there were a few problems that I had written down here and there so I figured this time why not keep a detailed journal. I've always loved the science behind growing. Although the harvest is of course my favorite part!

My first three grows I had about a 50% male female ratio. I was pretty blown away at how many turned out female. When doing this grow I told my wife I hope we only have six left because I don't think we'll have room for all of these if they're all female. We made it work! Hahaha

Something like this

Phosphoric Acid 85% - 1 Gallon - Uses: PH Control and Adjustment, Corrosion Inhibitor, Activating Agent, Personal Care, Pharmaceutical, Agriculture - Made in America - Alliance Chemical https://a.co/d/c6FRZWr

I put it in a smaller container to draw from. You can dilute it if you wish

Dude, you are amazing! I'll be sure to try this out today, it's watering day. I'll post updates and a couple days to a week. Thanks again both of you, such detailed and quick responses!