Indoor or outdoor, pH is buffered by the soil in less than 60 minutes. That's why slurry tests work.
LKV 420 Outdoor Grow Journal 2022
- Thread starter LKV
- Start date
lol ... don't get me going on slurry tests. that nearly fucked a 200 plant med grow about ten yrs back ..
coincidentally turned out the issue was inputs and ph ...
specifically it was the water source, we'd gone from well to municipal.. ph changed and everything went sideways. we were running hp and sunshine at the time with GH. even with ph under control it changed our nute inputs, though not drastically on it's own. we ultimately said to hell with it and went on RO. this was all indoor. there was no legal outdoor at the time.
we didn't corner the problem until we stopped looking at slurry, and thought about it from a different angle. previous to that i lived by output info. i can't run hempy that way either. it's all about the inputs. i screwed up with that when i first tried it too.
If your input water is shit it's tough for the soil to help you out, but like you found out, correcting the pH wasn't the answer.
Slurry testing doesn't tell you anything about your water, only the pH of your soil. And that's what the plant sees, not the pH of the water.
Slurry testing doesn't tell you anything about your water, only the pH of your soil. And that's what the plant sees, not the pH of the water.
didn't help us til the source water itself was fixed. it was needed after though.
ph was all over the map. zero consistency from bucket to bucket. didn't matter ph'ing going in or not. i'm pretty sure that's what prompted us to look at the water.
strange thing is we did bring a fairly decent harvest in while it was going on. another med grower tipped us off. he couldn't believe we got anything to finish. once the water was fixed and ph balanced we were good.
it was the very first time i'd ever run in to water specific trouble. i've lived a number of places and always under the assumption the water was a given.
- Thread starter
- #105
Watered my girls yesterday. I have one of 6 plants thats drooping leaves curling down heavy! I know there are many issues that can cause this. So because its was fine yesterday we can rule out underwateritn. All the plants are in the same area so we can rule out heat and wind issues. I recalibrated my PH meter and tested 2 of the girls today. the one with the curling is 5.15 ph and the rest are slightly higher in mid 5.5 range. the only thing i can think of is too much water but i watered it the same as the other ladies! Thoughts?
Two questions: aren't you in soil and did you use distilled water?
- Thread starter
- #107
yes fox farm ocean soil. i tested my tap water which is 6.8 then i added the soil to the tap and tested again
Two answers:
Slurry test need to be done with distilled water and the correct pH for soil is 6.3 to 6.8.
Let's see what the slurry test results are when done with distilled water.
Slurry test need to be done with distilled water and the correct pH for soil is 6.3 to 6.8.
Let's see what the slurry test results are when done with distilled water.
- Thread starter
- #109
got it, i have a water distiller making some right now, I'll post the results again with distilled.
For the record, here's the info on slurry testing, and it requires distilled water to work, and this is how to do it:
• Take samples from a few different places where there are roots (dig down a bit rather than just use the top - I often stick a spoon down the outside edge of the pot to grab some from there as well)
• Add an equivalent amount of distilled water as grams of soil (10 grams of soil, add 10ml water). If that doesn't make a slurry, use enough distilled water to make a stirrable-but-thick slurry.
• Stir it up, wait 15 minutes, stir again. After an hour put your calibrated pH stick in the water. That's the pH of your medium.
• Take samples from a few different places where there are roots (dig down a bit rather than just use the top - I often stick a spoon down the outside edge of the pot to grab some from there as well)
• Add an equivalent amount of distilled water as grams of soil (10 grams of soil, add 10ml water). If that doesn't make a slurry, use enough distilled water to make a stirrable-but-thick slurry.
• Stir it up, wait 15 minutes, stir again. After an hour put your calibrated pH stick in the water. That's the pH of your medium.
- Thread starter
- #111
ok I made distilled water but the PH is 5.92. is that ok or do i need to go out and buy distilled
water. I also have bottled spring water.
i just wanna see where this leads ...
as a guess i'd go with distilled is distilled
of course i had a smarmy response all lined up ....
as a guess i'd go with distilled is distilled
of course i had a smarmy response all lined up ....
5.92 is lower than it should be for soil, but a lower pH would mean higher uptake of micronutrients and that's not what seems to be showing in your leaves. The fact that it was fine one day and not fine the next tends to point more to a water or heat-stress issue.
Have you watered it to runoff lately?
If that's true, then she should run the test with her distilled water. Most pH meters come with a disclaimer that they cannot accurately read the pH of distilled water.
Why doesn't my pH Sensor read pH 7 in distilled or deionized water? - Technical Information Library
pH electrodes will NOT give accurate pH values in distilled or deionized water because distilled and deionized water do not have enough ions present for...
www.vernier.com
was literally about to post on this .. you should never use a ph tester with distilled water alone. really messes the bulb up.
which is one of the reasons i can't figure how a slurry test can be done without lab equipment. my dad used to test water and soil samples for years on various dam and irrigation projects.
Edit : sorry shed. not trying to shit on you ..
Just because a pH meter can't read plain distilled water has nothing to do with using that same meter to measure a slurry or pour-through test. But no need to take up this thread with that conversation.
- Thread starter
- #119
I watered it to"slightly" run off the evening before the drooping. thew water was just dripping out of the side/bottom holes. Its still drooping today. I ran the test again this morning. I used my home made distilled water and 2 tests from different batches and one on 5.12 the other was 5.19. Should I try to raise the PH? a bit?
- Thread starter
- #120
yes the distilled water is 5.92 not the soil