He’s in promix moisture control potting mix. Most store bought composts will have pH buffers so I doubt it’s a pH issue bro. I’m leaning towards temperature and/or over feeding.
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I would discard light burning 
, see no tacoing and lower fans are affected, I thought pH buffering in soil worked in large containers (15+ gallons). That soil has:
- Ground Limestone (for pH adjustment)
and limestone has an alkaline ph from 7.5 to 8, if you add that tap water with pH 7 no way to buffer that 
.
Could be fried by a nutrient burn, that’s why I would like to know those runoff stats … 
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Cut and paste.
Typically the pH of an unused PRO-MIX product that is 4-9 months old is 5.2-5.8 (S.M.E. method), depending on the product and the moisture content. A growing medium should be used within nine to twelve months of its manufacturing date to ensure that the pH of the unused growing medium is not too high.
Promix has enough feed within it to feed a plant for up to 9 months 
so it’s really looking like they are over fed. Personally I’d not feed them at all and just water.
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Thought you were and hydro man 
, so Promix is acidic and they add that limestone to adjust to a higher pH range? 
https://www.pthorticulture.com/en/training-center/low-ph-of-fresh-growing-media/
That’s why I don’t buy prefertilized soils, hard to control them, I guess you’re right and they could be overfed …
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I was under the impression promix has hardly nothing in it… you have to add the nutes… am I wrong here?? How about promix hp cc??
I grow in whatever I’ve got handy bro 
Hydro comes from my tap so it costs me sweet FA
My small tent is usually Coco coir but at the minute I’m growing some autos in store bought composts as the shop I bought it from is about 2 minutes from me compared to the closest grow shop that’s 3 miles away. I’m lazy what can I say
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Hey how do you supplement the coco coir? Do you add cal mag? And isn’t something higher in it as well naturally??
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FEATURES
- With MYCOACTIVE technology to stimulate vigorous growth for greater stress resistance, larger root system for increased nutrients, water uptake, bigger, healthier plants
- Enriched with a specially formulated plant food that gradually releases nutrients for up to 9 months
- Water less often with the included Coir / coconut fibre (Canada only) or Polymer Gel (USA only) that increases water holding capacity
As for Coco I add Epsom to my feed to add more magnesium as my tap water has enough calcium within it
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Worth mentioning that not all Promix is equal. The HP, for example, only has a modest starter charge. After a brief period, you have to fertilize or you’ll be in trouble. Not relevant to the Promix you’re speaking to, but more to @Terpsnpurps post. I don’t know about their coco, but I’d imagine it’s nearly, if not fully inert, similar to the HP.
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Yeah I have the promix hp cc it’s different… has 65 75 percent sphagnum peat moss … coir around 20 percent perlite ground limestone and dolomite wetting agent and mycorrihizae… inert… at least like the hp anyway… but I wanted to know… does that get treated like coco as far as ph?
. It is enriched with plant food that gradually releases nutrients for bigger blooms and vibrant colors
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OK that’s different than the promix I was talking about my bad… promix hp and promix hp cc is more a nutrient free medium
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Oh damn. I should have read the bag better I guess, I didn’t think there was any ferts in this mix. So it’s looking like hot soil. I’ll try to get some runoff using distilled water when I get a chance. I passed out last night and didn’t do it. Thank you everyone for your input!
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Did a runoff test on the Blueberry Cheese. Put in 6 pH water with 360 ppm, got 5.85 back out with ppm of 1086. Not sure how to interpret it exactly though. I’m guessing it’s dealing with calcium lockout due to low pH. Can I just flush it with higher pH water? My tap comes out about 7.5. Just don’t want this plant to be a complete waste of time.
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Don’t think there’s any Calcium issue, I would just water her with pHed water and no nutes and see how it reacts, seems the soil is too hot …
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