Need help understanding ppm using jacks 321 woth ro water

What can be causing this im stumped im using jacks 321 my ppm are coming out at 840 and my ph runoff at 6.0 in coco 70/30 but im only feeding 540 ppm because i had a high runoff almost 2000 ppm about 2 weeks ago i cant seem to keep it down so ive been feeding once a day everyday at half stength and still this problem lies)':


Samething with my girl in flower too checked it yesterday ppm was around 830 water at 540 ppm runoff today came back at 1100 and i water her twice a day?

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What does coco 70/30 mean?

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You’re runoff numbers now are fine to feed full strength. What size containers and how much water are you putting through? How much runoff are you getting?

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I’m guessing perlite by the pics.

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more than likely 70% coco / 30% perlite

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Increasing ppm of runoff simply means the plant isn’t taking in all that you are giving her. This is taken from Growweedeasy

I would not expect potassium deficiency with Jacks unless the mix is wrong. What are your per gallon mix rates.
Part A
Part B
Epsom

Do you throw in A first then add epsom salt?

If the plants need more potassium Part A needs to be increased.
Are you adding any microbes?

Are you certain pH readings are accurate? Wack pH can cause or magnify a lot of issues.

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Yes 70/30 is 70% perecent coco and 30% perlite
And i mix 5 gals of water at 18 grams part 12 grams part b and part e i give 6 grams
My runoff numbers were way over what i was feeding so i cut by 50% hoping something would change but no luck ppm in was way off what was coming out im talking 1900 when i feed only 540 ppm @beardless @Borderryan22

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I would personally just run distilled or RO to full soak and lots of runoff and make sure the ppm’s are low around 300. Then follow with a full strength feed ph’ed to 5.9. Then check numbers again. In coco with perlite you won’t overwater them.

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Did that tonight and my gdp was at 706 ppm she is the one in flower coming onto week 3 and the clones one was at 670 ppm and the other was at 957 and the ppm going in was 33 ppm @Borderryan22

Check scale that your meter measures on and make sure it’s apples to apples with ppm/tds/ec. In ro/distilled my 321 recipe is usually about 950ppm with two different apera devices.

Once that’s settled, you may just need to feed to a little more runoff. This provides rinse and reset.

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@dbrn32 what scale does jack use… just to be sure

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Exactly what you would expect from Jacks. It gives target amounts for all three. EC / 500 / 700

Guess my print out is outdated it doesnt have that 700 range and i see the feed is bumped up @beardless where did you get that from?.the website still has the outdated one

I don’t use recipe posted above, and my meter reads on 500ppm scale. When i mix 3.6/1.2/2.4 in ro or distilled is typically +/- 950ppm.

You run soil or coco?

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Coco. I would mix exactly same for soil though, just not feed as frequently. Tweak as needed from there.

Run that all the way through?

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Don’t run into calmag issues?

For the most part. I have been working on an additive that is basically a custom recipe i mix myself. I will tinker with adding this throughout grow for my own personal knowledge/info. I think recipe i use works pretty good by itself though. Some plants seem to like a little more epsom otherwise most issues I’ve seen have been due to environmental conditions or being lazy and missing feedings.

There’s always exceptions though too haha!

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I mentioned adding epsom above, that is for magnesium. Not really calcium issues though. Calmag relatively useless when using 321 recipe. You can adjust calcium by increasing/decreasing calcium nitrate and magnesium with epsom. Only other element commonly found in calmag is i think iron, and usually plenty of that in 5-12-26.

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