philbu said:

Yes, always use good, cross-referenced, ph pen, also periodically use the soil testing kit, the mix's pH is 7, and to refresh my memory with my excel sheet, the nuted water has been 6.3. According to the dutchmaster site you kindly offered, correct range is 5.9 to 6.5. Again, seems I'm in range and I would def consider raising pH above what's recommended if I had a clearer understanding as to why.

Thanks!

Click to expand...

@philbu
Over the years I have started using the practice of allowing a wide swing in my ph ranges. Timing will vary due to crop cycle, mediums used etc. I honestly believe that those growers that set to one specific ph range and never allow it to swing from low to high seem to experience more ph related nute deficiencies. For example, if I am running hydro ebb n flo the recommended range of my selected nute line is 5.2 - 6.0. So when mixing up a rez I will start at 5.2 to 5.3 and allow it to swing on up up thru 6.0. In my mind this allows for a more complete uptake of all the essential minerals and elements.

When I was always running a solid 5.8 and never let it drift was when I had the most problems. Thats just my 2 c and the method I use.

You might also want to check on your water sources alkalinity as well, because the alkalinity of your water will also factor in on your ph levels. Alkalinity doesn't seem to be discussed much and it is certainly a player in the whole water chemistry thing. Your Kh levels have a direct correlation to the buffering capacity of your water/ medium.

Heres a more detailed explanation...... The ‘K’ in KH comes from the German word 'karbonate'. KH is a measure of bicarbonate (HCO3-) and carbonate (CO32-) ions that act as buffers in the water to prevent the pH dropping or changing sharply (especially at night if you have plants in the aquarium). One degree KH is equal to 17.9 mg/I (ppm) CaCO3. It's also measured in degrees. The degree symbol may be replaced with a d (ie. 2 dKH)

you can do your own Kh test using a Kh test kit from any decent aquarium supply store. No need to send water out to a lab.

Here is a link that will explain alkalinity and ph better than I can. Take what you need and leave the rest. Peace

Had to remove the pdf file it was linking to my docs on my puter. not sure how that works. Heres a paste of it lets see if that works.

WATER ALKALINITY vs. pH – WHAT’S THE DIFFERENCE
Water alkalinity and pH are not the same. Water pH measures the amount of hydrogen (acid ions) in the
water, whereas water alkalinity is a measure of the carbonate and bicarbonate levels in water. Think of
carbonates and bicarbonates as dissolved limestone. The higher the alkalinity of the water, the more
lime it contains and therefore, the more rapidly the water can cause the growing medium pH to rise. On
the other hand, the pH of the water does not have any influence on the pH of the growing medium.
For example, the chart above shows the starting pH of two water sources and the amount of acid
required for each to reach a pH of 5.0. The water with the higher pH did not require as much as acid as
the one with the lower starting pH. At first glance, this may not make sense. However, note the
alkalinity in the center column. Regardless of the starting pH, the higher the alkalinity of the water
source, the more acid is required to reduce pH to 5.0. For all water sources, it is the alkalinity that
actually determines how much acid to use, not the pH.
How does water alkalinity influence the pH of the growing medium?
In the graph below, vinca plugs were grown for 49 days and constant fed with the same fertilizer at 125
ppm. The plugs were irrigated with three different water sources with varying alkalinities. The pH rose
in all three media samples partially due to the fertilizer used and the limestone in the growing medium.
However, the higher the alkalinity of the water source, the higher the pH of the growing medium.
This graph shows influence of the water
alkalinity on the pH of vinca plugs after 49
days. Notice the higher the water alkalinity,
the higher the pH of the growing medium rose
after 49 days.

Data taken from: D. Bailey & P.
V. Nelson, Substrate pH and Water Quality.
1996 Ohio Short Course
It is clear that the pH of the water and the alkalinity are not the same. In fact, the pH of the water does
not dictate the pH of the growing medium, but in fact it is the alkalinity of the water source that
influences the pH of the growing medium. This is important for growers to know since alkalinity has
significant impact on growing medium pH, choosing the correct fertilizer(s) and injecting acid, when
applicable.

Dang! Good explanation. :)

Seamaiden said:

Dang! Good explanation. :)

Click to expand...

Thanks @Seamaiden our aquarium knowledge can and does become useful even with plants.

Wish I could paste the chart/graph it helps put it all into relation being able to see the swings. Oh well Good to see you BTW.... :D

Seamaiden said:

Your mix reads a lot like soil to me, the plants are expressing signs of pH imbalance, and it probably won't hurt at this point to allow it to range higher. Or... possibly lower..? Hmm...

Click to expand...

Indeed... : )

Seamaiden said:

Ok, I see what you mean, due to the ProMix being in there. The perlite is inert, and if this were a pure perlite grow I'd be suggesting dropping the pH based on my experience with that. ProMix, even though I've got a bale, is something I haven't yet grown with. Still though, I think if you let it range up you might observe some positive changes. Then again, perhaps ranging it down might be the answer. But basically what I'm saying is that since you're stating you don't observe any pests, my next best guess here is pH. If the medium pH actually came out as a 7, then that's too high, it needs to be lower.

Click to expand...

Guarantee no pests, have experience with several of them.

Seamaiden said:

How did you test the pH of the medium originally? You mentioned you're using a good, properly calibrated meter (see below), so I'm curious about how you tested and whether or not it was pegged at neutral. I'm also curious about your source water.

Click to expand...

The source is tap water, stands at least 24 hrs while pumping air thru 2 stones. Tap's pH usually around 8.0 @ 150 ppm, temp in upper 60's.

Yes, luvurkle mentioned cheap pH meter. Mine, not so cheap. : ) Medium tests at 7.0 pH. That’s by way of the idiot Rapid Test probe, a soil test kit (capsules), a slurry test and the old gardener’s baking soda/vinegar test. Did testing at beginning and again a couple days ago.

I’ve never had pH issues before. Up or down? I could flip a coin. ; ) Or I could go for the 6.8. My only concern is that I’m half way through flower, now. Not sure how long it would take for me to notice any changes. I’m guessing there will be no change in worst damaged, maybe some reversal in less damaged?

There are 25 plants. 3 to 4 exhibit this issue through most of the plant. Counting those, there are roughly 36 limbs out of 350. So, roughly 10%. I could probably limp these across the finish line without much loss. But, I grow for co-ops, so want to do the best possible.

Seamaiden said:

If you posted it up, I apologize, I'm rather ADHD and tend to do several things at once.

Click to expand...

No prob. Know all about multi-tasking. : )

I fully understand the uncertainty, appreciate you going the extra mile. Perhaps it’s an odd mix, maybe go with choir and perlite next season, works great for me indoors, but I’ll look into all that. Now I'm going to read jumpincactus's next post a couple more times. : )

thnx!

here it is with the graphs.... thnx, still reading.....

Water Alkalinity vs pH - What's the Difference?
Water alkalinity and pH are not the same. Water pH measures the amount of hydrogen (acid ions) in the water, whereas water alkalinity is a measure of the carbonate and bicarbonate levels in water. Think of carbonates and bicarbonates as dissolved limestone. The higher the alkalinity of the water, the more lime it contains and therefore, the more rapidly the water can cause the growing medium pH to rise. On the other hand, the pH of the water does not have any influence on the pH of the growing medium.



For example, the chart above shows the starting pH of two water sources and the amount of acid required for each to reach a pH of 5.0. The water with the higher pH did not require as much as acid as the one with the lower starting pH. At first glance, this may not make sense. However, note the alkalinity in the center column. Regardless of the starting pH, the higher the alkalinity of the water source, the more acid is required to reduce pH to 5.0. For all water sources, it is the alkalinity that actually determines how much acid to use, not the pH.

How does water alkalinity influence the pH of the growing medium?

In the graph below, vinca plugs were grown for 49 days and constant fed with the same fertilizer at 125 ppm. The plugs were irrigated with three different water sources with varying alkalinities. The pH rose in all three media samples partially due to the fertilizer used and the limestone in the growing medium. However, the higher the alkalinity of the water source, the higher the pH of the growing medium.



This graph shows influence of the water alkalinity on the pH of vinca plugs after 49 days. Notice the higher the water alkalinity, the higher the pH of the growing medium rose after 49 days. Data taken from: D. Bailey & P. V. Nelson, Substrate pH and Water Quality. 1996 Ohio Short Course

It is clear that the pH of the water and the alkalinity are not the same. In fact, the pH of the water does not dictate the pH of the growing medium, but in fact it is the alkalinity of the water source that influences the pH of the growing medium. This is important for growers to know since alkalinity has significant impact on growing medium pH, choosing the correct fertilizer(s) and injecting acid, when applicable.

jumpincactus said:

Over the years I have started using the practice of allowing a wide swing in my ph ranges. Timing will vary due to crop cycle, mediums used etc. I honestly believe that those growers that set to one specific ph range and never allow it to swing from low to high seem to experience more ph related nute deficiencies. For example, if I am running hydro ebb n flo the recommended range of my selected nute line is 5.2 - 6.0. So when mixing up a rez I will start at 5.2 to 5.3 and allow it to swing on up up thru 6.0. In my mind this allows for a more complete uptake of all the essential minerals and elements.
When I was always running a solid 5.8 and never let it drift was when I had the most problems. Thats just my 2 c and the method I use.

Click to expand...

Yes, I do e&f indoors, as well. And my pH ranged from 5.7 to 6.2. So, why did it not occur to me that the same principal can apply to outdoor?? Looking now at past outdoor grow notes shows I didn't care (ha!) so much and I ranged haphazardly between 6 and 6.5 for soilless (no compost then) - no major issues, other than the bugs I killed. For some reason I got all twisted up over pH this round. This is an important point, thanks for raising it.

jumpincactus said:

You might also want to check on your water sources alkalinity as well, because the alkalinity of your water will also factor in on your ph levels. Alkalinity doesn't seem to be discussed much and it is certainly a player in the whole water chemistry thing. Your Kh levels have a direct correlation to the buffering capacity of your water/ medium.

Click to expand...

I get the gist of the article and will look into this more. I'll also check soil pH more to get a better idea of how water alkalinity, soil and water pH all relate to one another. Thanks a lot, jc, appreciate it. : )

phil

re-posted the article with the graphs for all to see

Seamaiden, thanks very much for you help. : ) You're right, it could be that pH needs to be lowered. But, barring any new info, I'm going to go with your other thought. I will try cycling regularly up and down between 6.3 - 6.8, maybe keep the high point through a couple waterings more than 6.3, 6.6 and see what develops.

phil

Keep the thread updated, I'd like to know how things progress. :)

That alkalinity vs pH thing is a difficult one to get the head wrapped around, at least, it was for me.

I'll do so, thank you : )

philbu said:

here it is with the graphs.... thnx, still reading.....

Water Alkalinity vs pH - What's the Difference?
Water alkalinity and pH are not the same. Water pH measures the amount of hydrogen (acid ions) in the water, whereas water alkalinity is a measure of the carbonate and bicarbonate levels in water. Think of carbonates and bicarbonates as dissolved limestone. The higher the alkalinity of the water, the more lime it contains and therefore, the more rapidly the water can cause the growing medium pH to rise. On the other hand, the pH of the water does not have any influence on the pH of the growing medium.



For example, the chart above shows the starting pH of two water sources and the amount of acid required for each to reach a pH of 5.0. The water with the higher pH did not require as much as acid as the one with the lower starting pH. At first glance, this may not make sense. However, note the alkalinity in the center column. Regardless of the starting pH, the higher the alkalinity of the water source, the more acid is required to reduce pH to 5.0. For all water sources, it is the alkalinity that actually determines how much acid to use, not the pH.

How does water alkalinity influence the pH of the growing medium?

In the graph below, vinca plugs were grown for 49 days and constant fed with the same fertilizer at 125 ppm. The plugs were irrigated with three different water sources with varying alkalinities. The pH rose in all three media samples partially due to the fertilizer used and the limestone in the growing medium. However, the higher the alkalinity of the water source, the higher the pH of the growing medium.



This graph shows influence of the water alkalinity on the pH of vinca plugs after 49 days. Notice the higher the water alkalinity, the higher the pH of the growing medium rose after 49 days. Data taken from: D. Bailey & P. V. Nelson, Substrate pH and Water Quality. 1996 Ohio Short Course

It is clear that the pH of the water and the alkalinity are not the same. In fact, the pH of the water does not dictate the pH of the growing medium, but in fact it is the alkalinity of the water source that influences the pH of the growing medium. This is important for growers to know since alkalinity has significant impact on growing medium pH, choosing the correct fertilizer(s) and injecting acid, when applicable.

Click to expand...

How the hell did you get it uploaded. I had a helluva time..... LOL

pdf's can be tough to work with, found an html version at pro-mix site: http://www.pthorticulture.com/en/training-center/water-alkalinity-vs-ph/
then a copy/paste : )

philbu said:

pdf's can be tough to work with, found an html version at pro-mix site: http://www.pthorticulture.com/en/training-center/water-alkalinity-vs-ph/
then a copy/paste : )

Click to expand...

u r da man my friend.... thank you

jumpincactus said:

For example, if I am running hydro ebb n flo the recommended range of my selected nute line is 5.2 - 6.0. So when mixing up a rez I will start at 5.2 to 5.3 and allow it to swing on up up thru 6.0. In my mind this allows for a more complete uptake of all the essential minerals and elements.

Click to expand...

Ding! Ding! Ding! We have a winner.

As the OP mentioned, s/he is NOT using soil. In fact MOST weed growers that say they are 'dirt farmers' are using SOILESS mediums. If you don't have things like CLAY and SAND in your mix, you are NOT using soil and should be using the soiless pH range. That has a SIGNIFICANT impact upon things like cation exchange in the rootzone, hence the higher pH needed for soil.

About 5.1 - 6.2, or so, is where you want to live. One caveat is heavy Sativa phenos - they have their own set of rules (but that is like 10%, MAX, of the strains out there).

Take that stupid assed pH chart of St0ney's that got plastered all over the forums (including this one) and throw in the f'in garbage. I watched that chart get made (probably close to 15 years ago), and know what brought it about - a dude who wasn't that good of a grower who also happened to be a Mod, so everyone wrongly and automatically thought Mod=Expert weed grower. It doesn't ...

Cat Jockey said:

Ding! Ding! Ding! We have a winner.


Take that stupid assed pH chart of St0ney's that got plastered all over the forums (including this one) and throw in the f'in garbage. I watched that chart get made (probably close to 15 years ago), and know what brought it about - a dude who wasn't that good of a grower who also happened to be a Mod, so everyone wrongly and automatically thought Mod=Expert weed grower. It doesn't ...

Click to expand...

interesting. more history lessons please

Your symptoms, crinkled/burnt leaves, seem to be broad mites. I read where you stated your sure there are no pest.

The fact that it appears on a single or random branch tells me it's not systemic.

I've seen and experienced this more than once unfortunately.

I read in another thread someone posted experiencing similar issues.

Broad mites thrive in cooler temps, 70 is perfect. Now that we are getting later into the summer temps are cooling down more into their optimal range. You see them in spring and late summer/early fall.
I spent a few seasons dealing with them and have gone down many a dead end trail chasing this.

The symptoms lead you to believe that it could be any number of nutrient/Ph issues. It's very frustrating and disheartening.

If you don't see some improvement after following up and applying the good advice in this thread I would be willing to bet it's broad mites.

I really hope I'm wrong. Having experienced their devastation I always get a knot in my stomach when I see these type of symptoms.

I second broad mites.

I appreciate the concern. I have checked multiple leaves, undersides, top sides and flowers with a 100x scope. Can see anything down to .01 mm. All I am seeing are immature trichs. I can guarantee, there are no Broad, Russet, Cyclamen, Two-spotted mites, or any other critter. I've dealt with bugs before and know how to spot them. : )

thnx!

Meantime, Cat Jockey, I'm reconsidering the soil/soilless question, based on reading through some university and gardening sites. I noted in my first post a medium consisting of Compost 30%, Promix 20%, Earthworm castings 20%, perlite 30%.

1) compost - organic material, yes - but not soil
2) pro-mix - not soil
3) castings - not soil
4) perlite - not soil

Terms and definitions can be used loosely, but professional and academic opinion seems to suggest that the above is soilless - at least from the amount I've read.

Just thinking out loud here.....

Cat Jockey said:

Take that stupid assed pH chart of St0ney's that got plastered all over the forums (including this one) and throw in the f'in garbage. I watched that chart get made (probably close to 15 years ago), and know what brought it about - a dude who wasn't that good of a grower who also happened to be a Mod, so everyone wrongly and automatically thought Mod=Expert weed grower. It doesn't ...

Click to expand...

I don't know who stoney is, but we deserve the best information possible.

It seems everyone and their brother has copied, in one form or another, E. Truog’s graph from his 1946 paper, Soil reaction influence on availability of plant nutrients. It’s academia’s go-to graphic for soil pH and nutrient uptake.





As far as nutrient uptake in soilless is concerned, North Carolina State University publishes this graph:




Here are the two graphs, together:

philbu said:

Meantime, Cat Jockey, I'm reconsidering the soil/soilless question, based on reading through some university and gardening sites. I noted in my first post a medium consisting of Compost 30%, Promix 20%, Earthworm castings 20%, perlite 30%.

1) compost - organic material, yes - but not soil
2) pro-mix - not soil
3) castings - not soil
4) perlite - not soil

Terms and definitions can be used loosely, but professional and academic opinion seems to suggest that the above is soilless - at least from the amount I've read.

Just thinking out loud here.....

Click to expand...

Soil, technically speaking, is a mix of things. As I mentioned previously, all you seem to really be missing from this mix, to make it 'soil' is the mineral component.

So, if you're confident in ruling out any kind of pest, and you're confident that your pH ranges are good, then the next thing to address would be disease. What diseases can cause these symptoms? Nothing I've observed to this point in my growing.