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Soil pH too high help!!

n1mbu5
n1mbu5started grow question 2 months ago
Guys I have a serious pH problem with my ladies in mid flower when I've been watering them the pH of the run off water has been 7ph but I left it over night and when more water drains out it's 8.7 pH. I flushed them with 5 pH water. It hasn't helped. Suggestions?
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Ultraviolet
Ultravioletanswered grow question 2 months ago
Fastest acting soil acidifier is aluminum sulfate, the aluminum reacts almost instantly to soft alkaline minerals. Grab some distilled water, no more tap water until pH rectified. 2-3ml per litre, every other watering. Tap water is normally just over a pH of 7, cannabis in soil likes 6-7 a little acidic. Whenever she gets a bit high give her a little dose and don't worry if you don't keep it precisely the same value, optimal uptake happens when it bounces around , 6.0, 6.5, 7.0, 6.2, 6.7
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m0use
m0useanswered grow question 2 months ago
How do the plants look? Soil ph can be a bit higher I find. If plants look ok, might be a none issue. Good advice by AsNoriu and Scrubbyjimbob on how to measure PH in runoff. Also last time your calibrated your PH pen?? might be wrong. I tend not to flush soil grows, normally means more issues for me.
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Scrubbyjimbob
Scrubbyjimbobanswered grow question 2 months ago
First, don't measure runoff like that. Salts will build up in your drip tray and spike your numbers. Pull a sample while it's draining. Think of a "clean catch" urine sample.....that's what you wanna do. Soil is pretty forgiving to pH imbalances compared with other media like coco. How do your plants look? Keep watering at your normal pH.
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AsNoriu
AsNoriuanswered grow question 2 months ago
In soil you dont flush. Feed you mixed, you use in 1-2 hours, ph drift for organic feed without extra air supply can happen. 7.0 run off is still ok. Loading 5.0 can make huge damage. Wet/dry cycle and loading right ph with runoff sorts out everything naturally.
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