"Runoff pH is useless" or "Keep an open mind"?

Creature1969

Creature1969

Well-Known Member
simpleleaf said:
The word "useless" means having absolutely no usefulness at all. "Not accurate" means something else.
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They're both the same outcome though. If you don't know how accurate something is, it's useless.
A hygrometer that reads 68% is useless if you don't know it's off by 4%. Technically, it's just not accurate, right?
A PH reading that's not accurate is the same deal. How useful is knowing a false PH reading?
 
Hollatchaboy

Hollatchaboy

Well-Known Member
simpleleaf said:
I'm sorry, I started the thread, and "runoff pH is useless" is logically not quite the same as "runoff pH is NOT ACCURATE!" The statements are similar, but your statement represents a slight moving of goalposts. The word "useless" means having absolutely no usefulness at all. "Not accurate" means something else.
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Watering to runoff is"not accurate", because it's "useless". There all better now. Lol

I will say this, in no till living soil, it's useless because you don't do it. If I'm just adding plain water everytime, why would I want to wash all the nutrient, that my microbes have worked so hard on making, out of the soil? Read the book teaming with microbes and you'll understand.
 
simpleleaf

simpleleaf

Well-Known Member
Creature1969 said:
They're both the same outcome though. If you don't know how accurate something is, it's useless.
A hygrometer that reads 68% is useless if you don't know it's off by 4%. Technically, it's just not accurate, right?
A PH reading that's not accurate is the same deal. How useful is knowing a false PH reading?
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My point was I may not have started the thread with that statement versus "runoff pH is useless". I'm not prepared to argue the point that runoff pH is not accurate. As I think about it right now, if I can manipulate runoff pH via the NO3:NH4 ratio, runoff pH may be more accurate than you have stated. But I'm not making a definitive statement, just thinking outloud.

Edit: Further, my personal goal is to set runoff pH at a value near input or nute pH. Whether that will make any difference in growing performance, I don't know. I guess that means I do believe runoff pH is accurate.
 
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OneMoreRip

OneMoreRip

Well-Known Member
Creature1969 said:
They're both the same outcome though. If you don't know how accurate something is, it's useless.
A hygrometer that reads 68% is useless if you don't know it's off by 4%. Technically, it's just not accurate, right?
A PH reading that's not accurate is the same deal. How useful is knowing a false PH reading?
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in my personal experience runoff ph testing has been accurate enough for me. For ph and ec

what method do you suggest for testing ph that is 100% (?) accurate?

as too the hygrometer example, it depends on the accuracy needed for whatever you are trying to achieve. If you only need to be within 10%, only off by 4 is fantastic
 
Wizzlebiz

Wizzlebiz

Well-Known Member
simpleleaf said:
Just because you and some other RIUers believe that's the case, no one on your side has proved it, rather just stated their beliefs and practices. When I say prove their case, I mean linking to a peer-reviewed science journal which states "runoff pH is useless" or similarly states it has "absolutely no use at all."

I have posted a link to a horticultural journal (way upthread) which I believe is peer reviewed which uses "runoff pH" as a data point, thus proving it has some usefulness. I have also posted a link way upthread to another grow site in which a poster who claims to be a scientist says runoff pH is a needed data point. But those links and the information in them have apparently not convinced you or your fellow believers that runoff pH as a data point has at least a little usefulness.

I'm reminded of the saying, "You can lead a horse to water, but you can't make 'em drink," though in this case, it might be more appropriate to say "You can offer a person a lit joint, but you can't make 'em inhale."
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Yea see this is where us informing you and you taking it upon yourself to do the research behind it comes into play.

We are not here to provide you everything you seek.

Ask a question, get an answer. Do your own research to figure it out from there.

Not our job bud.
 
Wizzlebiz

Wizzlebiz

Well-Known Member
OneMoreRip said:
stop acting butthurt. If you made the claim ph doesn't matter (for any growing medium), then support it.

Show me were I was informed about anything regarding run off, that I wasn't already aware of.

you are close to being on my ignore list as well, if you continue the odd behavior

Anyone saying I am giving people poor advice by telling them to make sure ph of the medium is good, then please show me the proof because I don't want to give bad advice. thanks!
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You are ignoring the reality that this is not the the thread topic was about.

Stay ignorant. Enjoy the bliss.
 
jondamon

jondamon

Well-Known Member
simpleleaf said:
I'm sorry, I started the thread, and "runoff pH is useless" is logically not quite the same as "runoff pH is NOT ACCURATE!" The statements are similar, but your statement represents a slight moving of goalposts. The word "useless" means having absolutely no usefulness at all. "Not accurate" means something else.
Click to expand...
The reason I said not accurate instead of useless is that it all depends on growing method.

with hydro “inert” or other “semi inert” media runoff EC can hold some useful information.

for example.

let’s say you’ve been over feeding coco.

your coco runoff is higher, much higher than the input solution, you can assume that the rootzone EC is going to be high too.

cause of action - reduce EC and increase pH slightly too help reduce the rootzone EC.

high EC runoff (crazy high) there would be little to no use testing it’s pH as it’s already got High salinity

If you’re in full hydro that’s why you test pH because there is no buffer in the medium to compensate so you keep pH between 5.5-6.2 only adjusting if the return water tests outside this range.

if your EC returns higher than it was set to then you reduce EC by adding water, then test and correct pH if it’s outside of range.
 
simpleleaf

simpleleaf

Well-Known Member
jondamon said:
The reason I said not accurate instead of useless is that it all depends on growing method.

with hydro “inert” or other “semi inert” media runoff EC can hold some useful information.

for example.

let’s say you’ve been over feeding coco.

your coco runoff is higher, much higher than the input solution, you can assume that the rootzone EC is going to be high too.

cause of action - reduce EC and increase pH slightly too help reduce the rootzone EC.

high EC runoff (crazy high) there would be little to no use testing it’s pH as it’s already got High salinity

If you’re in full hydro that’s why you test pH because there is no buffer in the medium to compensate so you keep pH between 5.5-6.2 only adjusting if the return water tests outside this range.

if your EC returns higher than it was set to then you reduce EC by adding water, then test and correct pH if it’s outside of range.
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Okay. It's always nice to have some nuance in between all the baloney that "runoff pH is useless".
 
xtsho

xtsho

Well-Known Member
I never check runoff pH. If you feed and water your plant properly you won't have any issues or need to be fiddling with out of whack pH and EC numbers. I just don't understand how so many people screw up such a simple task as growing a cannabis plant that they need to be checking runoff pH which by the way is highly inaccurate.

I've seen too many posts where someone has screwed up their plants because they checked runoff pH and the number wasn't what they thought it should be so they dumped a bunch of high or low pH'd solution on their plant to get the runoff to the number they think it should be.

The pH and EC of what goes in is all that matters. If you do that right you will be fine regardless of what you're growing in. Typically with soil you can just use tap water without bothering with pH. Testing pH used to be a hydro thing but now soil growers are fiddling around with it and in many cases are just causing problems by throwing the soil out of whack.

Many cannabis growers make growing more complicated than it needs to be.
 
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