Hi Family
I am 3 weeks into veg, growing photo skunk in coco/perlite.
Looking for advice on feed and run-off EC and PH levels.
This is my first indoor grow. I am feeding at 1.5 EC 6.0 PH. My run-off is 0.7 EC and 6.5 PH.
From what i gather its all about the run-off as that is a product of what is happening in the roots. What should i be targeting for run-off numbers or have i got this all wrong?
Plant is looking great and shows no signs of any deficiencies. Just wanting to get my head around this in case i could be doing better
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Iâll tag along if you donât mind. As soon as my current grow is over, Iâll be switching from soil to coco/perlite.
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My basic understanding is that if you get the PH right, the plant will take in the nutes. I think i have a good PH in and out numbers
ATM 1.5 EC in and 0.7EC out tells me plant is taking in 0.8EC
If i increase EC, will plant take in more? Or should reduce and save on nutes etc
If youâre using the 500 scale then 1.5ec =750ppm.
If your ec is 0.7 coming out then your plant is eating good.
Your PH going in is good. I try and get closer to 5.8 myself. I wouldnât worry about the runoff PH. Youâre within a half a point. Iâd worry if you were over 7 coming out.
What size pots you in? Are you feeding to 20% runoff?
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I wouldnât change anything until your plants tell you something is wrong. Got any pics?
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Your plant looks great my friend. I wouldnât change your ppm until you flip to flower then you can bump it up.
How often are you feeding? Do you have a good runoff when you do?
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Perfect! Youâre right on bro.
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@The_Chef
I was feeding at 1.1 EC. Then added some more nutes according to the schedule but that mix came up to 2.2 EC. I watered down to 1.5EC i just thought that was too much. The schedule said it should be 1.2EC but was nowhere near that. Week 3 Veg
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[quote=âForthefunofit, post:1, topic:87564â]
run-off as that is a product of what is happening in the roots
[/quote
This from CuriouscultivationsâŚcomâs article
RUNOFF PH: EXPLAINING THE BRO SCIENCE
I found it to be helpful deciphering this mystery. The summary describes Extreme pH as a change of 1.0. In coco I believe that is to big a swing. I go with a change of .5 or more. For soil that may be OK because of soil buffering capacity. That is not the case with coco.
I for the most part follow KootMeds hydro pH recommendation. It is much less generous than some other charts
For comparison, this chart if from Growweedeasy
Like @The_Chef my target feed pH is 5.8. I use Jackâs 321 formula. It does not contain pH stabilizers. I do not recall my runoff pH dropping very much below that. However, due to my water and supplements, it has risen to over 6.4 a couple weeks into flower. I flushed to bring it down and this stopped any further nutrient deficiencies occurring due to lockout.
These pH numbers may not apply to you because of the pH stabilizer in Dual Fuel. Keep monitoring the runoff and correlate its changes with how your plant reacts.
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Coco should be fed daily and to ample (20%) run off with a PH of 5.8-6.2. I start with seedlings at 500 PPMs 1.0 EC then bump that up 100 PPMS each week with a PH of 5.8 in veg and finish veg and start flowering at 1000 PPMs and I increase the PH to 6.0-6.2 in Flower. The run off is critical to wash away any un-used salts and minerals from the previous feeding that could accumulate in the root zone causing issues. With coco itâs the same routine every day 
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@OGIncognito
I am about to flip to flower. In the last 4 or 5 days i have upped my EC to 1.6 and 5.8PH.
My run off is 1.4EC and 6.1PH.
My thoughts are than my Runoff EC should be lower. Am i feeding too high EC?
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Those numbers are in range and PH is on point. Water feed the next round with silica and calmag to get your EC around 1.2. Nice job Growmie . Here was my starting PPMs on some coco loco Iâm using on a simple small run
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Hey Growmie, I got this backwards⌠I just woke upđ. Anyway that EC would have you around 700 PPMs so an EC of 1.4 is low. Feed at 2.0 EC which comes out to around 1000 PPMs
@OGIncognito
This is the numbers i was expecting. Last week i was feeding 2.0EC and getting 1.6EC run off. So i lowered feeding to 1.6-1.7EC as I thought there seemed no benefit to have EC that high with only 0.3EC uptake.
My plant is extremely healthy so i have no worries there, just want to nail down the feeding and see a decent nutes uptake.
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Plants look great Growmie, The 300 difference was a good sign their eating.
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