Interesting Article regarding PH

Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
thats a pretty pointless experiment, they don't say what kind of water they used, what the ppm were before they started adding anything to it, and it was specific to their nutes. all it means is their nutes are ph correcting...and if you correct them yourself, the built in buffers will change whatever you do once you pour it in your pots
 
BobCajun

BobCajun

Well-Known Member
Actually the optimal range stated in most hydro references is the low sixes, around 6.25 being best. You can look at the charts that show nutrient availability and you can see that 5.5 is low enough to reduce availability of certain nutrients. Here's one for the major three only, since virtually all nutrient brands now use chelated micros which aren't affected much by pH.The chart clearly shows that 5.5 is too low and even 6 is too low. They don't show between 6 and 7 though. Though it shows 7 to be best, pH tends to rise as nutrients are used up. So it's best to start a little low. 5.5 is so acidic that I'm pretty sure it must hard on roots.

Personally, I never adjust pH at all. It's a perlite medium watered once daily, reusing the runoff a few times by adding water to dilute it or more nutes to enrich it to get it back to the right ppm level. Using deionized water and AN or Flora Nova nutrients, every time I've tested it the pH was right in the proper zone, meaning low to mid sixes. Those brands do have pH buffers in them though. Might as well buy brands with buffers and make things easy for yourself.


source
 
Last edited:
Dr. Who

Dr. Who

Well-Known Member
BobCajun said:
Actually the optimal range stated in most hydro references is the low sixes, around 6.25 being best. You can look at the charts that show nutrient availability and you can see that 5.5 is low enough to reduce availability of certain nutrients. Here's one for the major three only, since virtually all nutrient brands now use chelated micros which aren't affected much by pH.The chart clearly shows that 5.5 is too low and even 6 is too low. They don't show between 6 and 7 though. Though it shows 7 to be best, pH tends to rise as nutrients are used up. So it's best to start a little low. 5.5 is so acidic that I'm pretty sure it must hard on roots.

Personally, I never adjust pH at all. It's a perlite medium watered once daily, reusing the runoff a few times by adding water to dilute it or more nutes to enrich it to get it back to the right ppm level. Using deionized water and AN or Flora Nova nutrients, every time I've tested it the pH was right in the proper zone, meaning low to mid sixes. Those brands do have pH buffers in them though. Might as well buy brands with buffers and make things easy for yourself.


source
Click to expand...
A, BOB - THAT'S a SOIL chart! Not only that but, different plants will "set" the soil to it's pH needs.....as much as it can. Acid loving plants will grow in a normal and even a lower acid soil. They just won't preform as well.

Hydro should be in the 5.8 to 6.2 zone. I would adjust to 5.8 and let her ride up to 6.1/6.2 and readjust back to the 5.8 again.

Different nutrients are "most" available at differing pH values. this is true for soil and hydro!
Soil swings naturally. In hydro, allowing the swing always seemed to give me better uniform results.
 
BobCajun

BobCajun

Well-Known Member
Dr. Who said:
A, BOB - THAT'S a SOIL chart! Not only that but, different plants will "set" the soil to it's pH needs.....as much as it can. Acid loving plants will grow in a normal and even a lower acid soil. They just won't preform as well.

Hydro should be in the 5.8 to 6.2 zone. I would adjust to 5.8 and let her ride up to 6.1/6.2 and readjust back to the 5.8 again.

Different nutrients are "most" available at differing pH values. this is true for soil and hydro!
Soil swings naturally. In hydro, allowing the swing always seemed to give me better uniform results.
Click to expand...
Whatever dude. Since there are buffered nutrients available and I use them I don't really have a reason to care.
 
Dr. Who

Dr. Who

Well-Known Member
BobCajun said:
Whatever dude. Since there are buffered nutrients available and I use them I don't really have a reason to care.
Click to expand...
Roger A. Shrubber said:
i think you're wasting your time. some people are worth teaching, and some are a black hole you can pour knowledge down and it just fucking disappears forever
Click to expand...
:wall::wall::wall::wall::wall::wall::wall::wall::wall::wall::wall::wall::wall:

Oh please send us some pictures of your buffered nute use hydro at 7 pH...... I'm sure we would all like to see that!
 
BobCajun

BobCajun

Well-Known Member
Dr. Who said:
:wall::wall::wall::wall::wall::wall::wall::wall::wall::wall::wall::wall::wall:

Oh please send us some pictures of your buffered nute use hydro at 7 pH...... I'm sure we would all like to see that!
Click to expand...
It's a miracle. But when did I say it stays at 7? I said it stays in the sixes, which is exactly where it should be in my system. References say 5.8 is best for hydroponics but I find that anywhere in the sixes works well and I don't need to do anything to maintain that. You might get slightly more nutrient availability at 5.5-5.8 but it's probably not worth the trouble of adding acid all the time.
 
Last edited:
BobCajun

BobCajun

Well-Known Member
It's actually not that important what the exact pH is, as long as it's between 4 and 7. A pH of 6.8 is just what is usually aimed for. The following is from a pdf entitled "Nutrient Management in Recirculating Hydroponic Culture, Bruce Bugbee Crop Physiology Laboratory Utah State University".

"pH Monitoring and Control
Is pH control important? Most people assume pH control is essential, but there is considerable misunderstanding about the effect of pH on plant growth. Plants growequally well between pH 4 and 7, if nutrients do not become limiting. This is because the direct effects of pH on root growth are small, the problem is reduced nutrient availability at high and low pH. The recommended pH for hydroponic culture is between 5.5 to 5.8 because overall availability of nutrients is optimized at a slightly acid pH. The availabilities of Mn, Cu, Zn and especially Fe are reduced at higher pH, and there is a small decrease in availability of P, K, Ca, Mg at lower pH. Reduced availability means reduced nutrient uptake, but not necessarily nutrient deficiency.

How Important is Maintaining pH 5.8? We control the pH at 4 to study root respiration (to eliminate bicarbonate in solution). We compared growth at pH 4 and pH 5.8 with wheat and were not able to find a significant difference in root growth rate or root metabolism. We now routinely grow wheat crops at pH 4 during the entire life cycle. However, although there is usually a broad optimum pH, it is still best to maintain pH at about 5.8 to optimize nutrient availability. pH levels below 4 may start to reduce root growth, in one study our pH control solenoid failed Just after seed germination and the pH went to 2.5 for 48 hours. The roots turned brown and died, but new roots quickly grew back and the plants recovered."
 
Dr. Who

Dr. Who

Well-Known Member
BobCajun said:
It's actually not that important what the exact pH is, as long as it's between 4 and 7. A pH of 6.8 is just what is usually aimed for. The following is from a pdf entitled "Nutrient Management in Recirculating Hydroponic Culture, Bruce Bugbee Crop Physiology Laboratory Utah State University".

"pH Monitoring and Control
Is pH control important? Most people assume pH control is essential, but there is considerable misunderstanding about the effect of pH on plant growth. Plants growequally well between pH 4 and 7, if nutrients do not become limiting. This is because the direct effects of pH on root growth are small, the problem is reduced nutrient availability at high and low pH. The recommended pH for hydroponic culture is between 5.5 to 5.8 because overall availability of nutrients is optimized at a slightly acid pH. The availabilities of Mn, Cu, Zn and especially Fe are reduced at higher pH, and there is a small decrease in availability of P, K, Ca, Mg at lower pH. Reduced availability means reduced nutrient uptake, but not necessarily nutrient deficiency.

How Important is Maintaining pH 5.8? We control the pH at 4 to study root respiration (to eliminate bicarbonate in solution). We compared growth at pH 4 and pH 5.8 with wheat and were not able to find a significant difference in root growth rate or root metabolism. We now routinely grow wheat crops at pH 4 during the entire life cycle. However, although there is usually a broad optimum pH, it is still best to maintain pH at about 5.8 to optimize nutrient availability. pH levels below 4 may start to reduce root growth, in one study our pH control solenoid failed Just after seed germination and the pH went to 2.5 for 48 hours. The roots turned brown and died, but new roots quickly grew back and the plants recovered."
Click to expand...

First off. Wheat isn't MJ! They also have differing pH needs in soil. Wheat needs VERY high N levels. MJ does not. I farm organic wheat, oats, rye and corn. They're all grain plants but, they all run differently!

Secondly. there are guys around here that would say YOUR full of shit and that you need to keep the pH levels in hydro LOW at like 5.5 to 6.0 and quote that same paper your posting here.

Lastly......Do what the fuck you want! I just don't care for your propensity to spout BS and affect new growers with not the best practice......I say your flat out LAZY for NOT adjusting pH PROPERLY. The posting of a soil pH chart and talking about hydro is simply WRONG! BTW, YOU said that a pH of 7 was "best" - your first post - line 4.........

In decades of growing. I can say without ANY doubt! Use the "swing" in pH to get superior, uniform results, faster! pH hydro to 5.8 - 6.2 and a tenth of a point extra in either direction. Will not hurt on the odd occasion.

Not every paper written on growing, applies to every plant.
 
Last edited:
Dr. Who

Dr. Who

Well-Known Member
Jeffro420 said:
Haha
Click to expand...
It does Jr. You fell for big glossy cartoon labels, overstated claims of it being "cannabis specific" (NOTHING is) and you pay for watered down nutrients that have too many supplements that do the same thing or basically nothing - depending on what you buy!

Their products create more growth in their bank account, then in your garden!

You can do BETTER, with LESS, FOR less!

Bottom line. AN is CRAP!
 
Olive Drab Green

Olive Drab Green

Well-Known Member
Dr. Who said:
Oh yes, I forgot to say this! While they work......

AN still sucks!!!
Click to expand...
Not to stir the pot, but I just want to enlighten those who are unaware that the one co-owner is a pedophile and child rapist. Just something to consider when your money can be considered your endorsement. Not that I necessarily always agree with that, either, but it's fact that in some contexts, it constitutes endorsement.

Still loving the quality of Roots Organic's Dry Nutrient system.
 
Last edited:
Olive Drab Green

Olive Drab Green

Well-Known Member
I would recommend most people (anyone, but especially if you are organic or could cope with switching to organic without personal resistance, although I suppose they make dry synthetics, too) switch to dry nutrients. When you buy liquid, you're paying for mostly water with the nutrition dissolved or suspended in it. Buying dry nutrients, you can mix up your own, or make a tea for the organic crowd, if not just top dress and amend. Don't waste money on water, get a purer form.
 
You must log in or register to reply here.
Top