pH 6.96, yellowing leaves

Hello, I could use some advice on my issue: yellowing leaves, pH <7 but barely, no insects or mold observed. Below are the growing conditions. I repeatedly tried to load images, but only the file would load. The MKU also has some purpling of the leaves, not sure if that is a normal variant or a nute issue?

STRAINS: Gorilla Glue, MK Ultra, Blue Dream (BD is about a week younger than other two)

Growing in 5 gal fabric pots, Fox Farms Ocean Forest soil

pH OF RUNOFF: GG 6.96; MKU 6.87; BD 6.56

pH OF H2O: 6.73 (well water)

NUTES: Fox Farms Big Bloom 3 tsp/gal. + Fox Farms Tiger Bloom 2/tsp/gal., used every other watering (followed Fox Farms feeding schedule).

TEMP/HUMIDITY: 70-76F, RH <60%

Flipped to 12/12 on 2/18/21.

Not sure why, I can’t get any images to load, just the file.

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Not sure ph is gonna be your issue. You didn’t list if you’re supplementing and calcium or magnesium. Fox farms nutes are light on both, especially magnesium. Would think about adding in 1/4 teaspoon of epsom salt to your water on your water only days.

No I am not supplementing with cal/mag but I do have some so I will try that out. Thanks for the input!

I like to use epsom salt in flower. Unless you have a calmag that is low in nitrogen.

I have General Hydroponics CALiMAGic 1-0-0. It does contain 1% total N, would that be too much? I do have Epsom salts, too, if that would be better.

As I mentioned in my OP, we have well water and add softener salts, could this be messing things up? Now that the threat of freezing temps is over I have set up my rain barrel, which is the water I usually use.

Not sure how the softener will interact with the plants but it looks like the typical lack of magnesium that fox farms nuted plants get. That calmag isn’t high in nitro so you can definitely use it.

Thank you for the advice, Bobbydigital, I am most grateful! I’m going to hit up my girls now, wish me luck!

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Hey Chinacat 420! Typically you want the rootzone pH in a range of 6.0-6.5. When you start to get higher than 6.5, nutrients will start to become unavailable to the plant (especially micro nutrients). You can try mixing your nutrients, test the pH, and lower it using pH down or a mineral acid to around 6.3. This should help lower the pH in the rootzone making the nutrients more available to your babies! Just some tips I’ve learned from the past :slight_smile:

Hey Jazzcabbage, thank you for replying to my post, I really appreciate it! I just put your advice to use, so :crossed_fingers: I only got a few weeks left so hopefully that’s enough time for them to bounce back. I’ll definitely remember your and Bobbydigital’s posts for my next grow. This was my second, so as they say “third times a charm”! :sunglasses:

Awesome man! Let me know how it goes :slight_smile: haha 3rd times the charm is right! The great thing about growing, is you get better each grow and eventually it will all be muscle memory :+1:

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