Very low ph readings in run off

I started a grow 3 weeks ago using promix and GH nutes. First time using promix and
since day one my run off ph has been around (4.8-5 ) even though I was watering with 6.5 and wasn’t really worried since the promix guys say on there site it sometimes takes promix up to 2 weeks for the mixes ph to level out but it hasn’t. Ive tried uping my intake ph water (8-9)to get it to rise to the level it should be (5.8-6.3)with no luck. Plants are slow growing and not eating like they should,I’ve never went more than 3-4 weeks in veg before flipping. What can I do to correct this problem,if there’s nothing I can do I’m gonna just scrap this grow and start using another medium but I know if there’s an answer I’ll get it on here
Thanks

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I’ve never used promix but I hear it mentioned alot on here. @Covertgrower @CoyoteCody

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@Myfriendis410 is a promix guru.

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Thanks guys I’ll wait for others to chime in.

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Have you got a pic of the bag.
They have a few different mixes.
I use the sunshine mix and no issues with any of my grows due to an off mix.
:v:

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@Oldguy
Bought it at a Walmart. I was gonna switch over to Coco after my last grow but this caught my eye one day while
I was there. My gut told me not try it but I did, other than the ph issues though it seems to be good.

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@Wllbuckhunter1971
From the looks of it that feeds for 9 months.
So it’s already loaded up with nutes.
And likely at the incorrect ph for weed plants.

image
This is what I use.
Starter charge of nutes for a seedling but after a few waterings they’re pretty much depleted.
This way I control what goes into my plants.
And no surprises with ph going south. :wink:
With a bigger pot it’s good for a 4 + month grow without issues.
You could add some dolomite lime to the top of your pot and just water it in. That will raise your medium ph but it’s a bit slower acting.
And with the nutes in it you will probably have a few issues when you transition to flower.
Too much of one nute and not enough of another.
Hope this helps a bit
:v::pray:

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@Oldguy
Yes it does help,I’ll get me some dolomite lime today and top dress it in. Hopefully that’ll bring the ph up a bit. Someone on another site said I could use ground up egg shell also, have you ever heard of that?
I put some promix right out of the bag in a solo cup by itself and waterd with distilled water to see just how much nutes were in it. I got 300 ppm from the run off and 5.4 ph so it doesn’t have alot of nutes in but I can’t understand how the ph came out that good unless some of the nutes I’m putting in it is having an effect on it. I make sure the ph is correct going in though so I don’t know. Here is everything I’m using

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Egg shells will work but a lot slower acting than the dolomite lime.
And what you’re using for nutes is good.
@Myfriendis410 is familiar with those more so than I am. :+1:
:v:

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Alright thanks, you think it would be Okay to dissolve whatever amount of the lime it calls for in a few gallons of correct ph water for a faster response or just top dress them

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Yeah; unfortunately that’s their commercial potting soil (like Miracle Gro) and should not be used for cannabis.

The Promix you want is a nutrient-free medium like coco that you have to supplement for through the entire grow. Not really sure what you can do about your situation now. Dolomite lime would help but I’d get a runoff TDS to confirm high salts content and that is what’s stalling your babies out. I’d guess your numbers will be in the three to four thousand ppm range.

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No nutes in the ProMix he’s using. It’s sphagnum and coco. I use the same stuff.

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There is nothing on the pack about nutrients. It’s sphagnum and coco.

They aren’t telling you everything in it. The list they show is for a nutrient free medium and that’s listed as soil. It also has a moisture retention additive which is no bueno for weed. PH is low as stated: it’s not suitable for cannabis.

This is from their website for the product:

This high-quality peat-based mix is perfect for all indoor and outdoor container planting, re-potting or seed starting. This potting soil provides the best results, thanks to PRO-MIX’s exclusive technology that stimulates stronger roots and provides healthier plants. It is enriched with plant food that gradually releases nutrients for bigger blooms and vibrant colors. You can also count on the natural coco fibre to increase moisture retention; therefore, you spend less time worrying to water your plants. This compressed pack contains 2 cu. ft. of ready-to-use mix in a recyclable bag, an ecological choice using 2x less bags. So you can enjoy gardening all year long!

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Where did you find that? Because this is what I got from the page for that mix. Nothing about food.

Ive been using the same soil because it doesn’t have nutes already in it…couple grows in it now with GH nutes… works :+1: I add 30% perlite to it…all the buckets mixed exactly the same…7gal pot 1 3/4 gal. gives slight run off…water every other day under 1000watt HID…straight water ph’d every 4th watering…grows beautiful canabis…Happy Growing