PH of the water changes by itself...?

[iogrow]

Hey ppls, is it normal for this to happen: Normally when I water my plants I just fill a 1.5 Litter bottle with tap water, check the pH with a GHE test kit, most of the time the PH is higher than 8, then I use vinegar to lower the pH to around 6,3-6,7. Now I dunno what happens, but when I check the pH of this water the next day its at 8 again, how can this happen?

 

[Guest]

vinegar doesnt hold over long periods, get yourself some phosphoric acid aka real deal ph down

 

[Guest]

or nitric acid

 

[iogrow]

vinegar doesnt hold over long periods, get yourself some phosphoric acid aka real deal ph down

I sure will

Still, does the vinegar hold for enough time for me to water the plants right after lowering the pH with it? I mean will the roots have enough time to absorb the water and nutes b4 the pH rises again?

 

[Guest]

it isnt really reliable enough to use in that manner, it probably starts breaking down the second you put it in

 

[iogrow]

darn

thanks people. Now I only hope I don't have to go to a grow shop to get some of that phosphoric or nitric acid.

btw. vinegar was recommended to me by the dude at the growshop

 

[Guest]

Depending on what precisely is making your water's pH 8+, you may NEVER get water where the pH is stable

And neither phosphoric acid, nor nitric acid will do much, if any, better than vinegar or lemon juice.

The basic problem is buffering. Your water will always try to go back to what its original pH was.

pH instability is why I converted my hydro gro to soil. I just could not keep my pH stable more than a day or two. I have high pH water here too.

pH of your water in a soil grow is pretty much a non issue IF, and I stress IF, you have a properly made up soil mix. The plants you see of mine in the pics below have been watered with un treated tap water since they were put into pots and I went 12/12 back in mid April. They are the picture of health IMO. I expect a good harvest.

Make up a good soil mix like in the Organic soil section Sticky Note by BurnOne and you can water without worries. Maybe make up new soil for your next transplant?

Good luck
Obli

One of my Ice plants on Day 37 of flower



My girls on Day 40 of flowering

 

[iogrow]

Depending on what precisely is making your water's pH 8+, you may NEVER get water where the pH is stable



The basic problem is buffering. Your water will always try to go back to what its original pH was.

hmm, that's interesting. It will try to go back, that means its got some serious chemicals in in

I've just checked the water I diluted with vinegar around 8 hours ago, it's got a pH of about 7,5-7,9 already.

Funny why I have not read about this issue anywhere and I've browsing different forums for a while now

p.s. I'm growing in Plagron Grow-Mix soil (pH: 5,8 and 6,2 / EC: 1.4 and 1.6)

 

[clowntown]

it isnt really reliable enough to use in that manner, it probably starts breaking down the second you put it in

Yup that's exactly what I experienced as well on my last run, when I ran out of phosphoric acid and tried vinegar as pH down.

 

[iogrow]

Does it have to be pure phosphoric acid or could I use something I can get at the pharmacy?

Where does one usually get pure phosphoric acid?

 

[Guest]

dont try to cut corners on everything...ph up and down are vital tools in any growers arsenal...order some or go to your local hydro shop

 

[iogrow]

the problem is that there only one local grow shop, and I don't want to go there anymore, I've been there a couple of times buying stuff for growing, maybe I'm being paranoid, but still, better safe than sorry. And I don't want to order to my address, I could use a friends, but that will probablly take a week, so that's why I wondering if I could get it in a "normal" store. Maybe I should go to a chemist store....

 

[clowntown]

If it makes you feel better, have a friend buy you a bottle. It'll last you a long time.

Most commercially available "single bottle pH down" solutions are phosphoric acid; some companies have two separate versions of pH down: phosphoric acid for use during flowering, nitric acid for use during vegging. Not sure how much using nitric acid vs. phosphoric acid during veg helps, but just something I've noticed.

Seems folks have used sulfuric acid (see car battery) successfully as well.

And isn't the Earth Juice natural pH down citric acid crystals? Would citric acid (lemons, etc) work? All I know is that vinegar doesn't...

 

[Guest]

You say you're using GHE test kit?Not sure what that is but GH Ph test kit comes complete with up down and indicator,a little dolomite in your soil mix and thats all you need for soil grows.Man up and go to the damn store lol

 

[Guest]

hmm, that's interesting. It will try to go back, that means its got some serious chemicals in in

I've just checked the water I diluted with vinegar around 8 hours ago, it's got a pH of about 7,5-7,9 already.

Funny why I have not read about this issue anywhere and I've browsing different forums for a while now

p.s. I'm growing in Plagron Grow-Mix soil (pH: 5,8 and 6,2 / EC: 1.4 and 1.6)

Hi again:

This is probably more explanation than you wanted. It depends on your educational background in chemistry. Mine is pretty good. I also spent a career working with pH measuring instruments...among many many other instruments I had to learn to use and fix.

Try reading this web page and maybe some of the related references. Here is part of it that may make sense to those who are "non technical weenies". I was a techincal guy for a long time. Now I just work a regular job and smoke pot And have one hell of a lot of fun doing it.

http://en.wikipedia.org/wiki/Buffer...uffering_effect:_Sodium_acetate.2Facetic_acid

Here is the partial quote from the web page above. The emphasis in color is mine:

Applications
Their resistance to changes in pH makes buffer solutions very useful for chemical manufacturing and essential for many biochemical processes. The ideal buffer for a particular pH has a pKa equal to the pH desired, since a solution of this buffer would contain equal amounts of acid and base and be in the middle of the range of buffering capacity.

Buffer solutions are necessary to keep the correct pH for enzymes in many organisms to work. Many enzymes work only under very precise conditions; if the pH strays too far out of the margin, the enzymes slow or stop working and can denature, thus permanently disabling its catalytic activity. A buffer of carbonic acid (H2CO3) and bicarbonate (HCO3−) is present in blood plasma, to maintain a pH between 7.35 and 7.45.

Industrially, buffer solutions are used in fermentation processes and in setting the correct conditions for dyes used in colouring fabrics. They are also used in chemical analysis and calibration of pH meters.


Here is another reference that may help because it can get confusing:

http://en.wikipedia.org/wiki/Buffering_agent

Check out this partial quote from above:

Buffering Agents Vs. Buffer Solutions

Buffering agents are similar to buffer solutions as a result of the fact that buffering agents are the main components of a buffer solution. They both regulate the pH of a solution and resist changes in pH. A buffer solution maintains the pH for the whole system which is placed into it, whereas a buffering agent is added to an already acidic or basic solution, which it then modifies and maintains a new pH.


[edit] Conclusion
Buffering agents and buffer solutions are almost one and the same except for a few differences.

Solutions maintain pH of a system, preventing large changes in it, whereas agents modify the pH of what they are placed into
Agents are the active components of a buffer solutions
Monopotassium phosphate (MKP) is an example of a buffering agent. It has a mildly acidic reaction; when applied as a fertilizer with urea or diammonium phosphate, it minimizes pH fluctuations which can cause nitrogen loss

 

[iogrow]

hey thanks 4 da info Oblidio49

So I guess my water supplier is adding a buffer solution to keep the pH at around 8

I just need a stronger buffering agent

 

[Guest]

Welp - here's the quick solution to your issues.

Buy some dolomite lime (over the web if a must, or at local nursey/hardware store). Add 2tbsp's per gallon of soil.

After that's mixed in your run off should stay at a near constant as the lime buffers what your water wont.... at least that's my understanding and use of lime.

 

[Guest]

Thats true.With properly limed soil your runoff and soil ph will read around neutral.I personally adjust my nute ph only because of soil ph "drift" concerns when too much low or high ph liquid is introduced into the soil.I dont know how long it would take for soil PH to "drift",what parameters would cause it to drift(below 5 above 9..)or even if soil ph drift actually occurs.Its one of those things I've wondered about,but never really tested.When using the same ferts and the same water,PH adjustment becomes kinda blindly automatic

 

[Guest]

hey thanks 4 da info Oblidio49

So I guess my water supplier is adding a buffer solution to keep the pH at around 8

I just need a stronger buffering agent

No you don't need a stronger buffering agent. You need to lime your soil as suggested by soilman and others above.

I doubt the water company puts anything in your water. The naturally occuring Calcium, magnesium, and maybe iron are usually responsible for higher pH.

The real problem for growers who have water like I have and poster had is if you are doing a hydro grow. And IMO using distilled or RO water is the only solution. Too spendy for me.

 

[Guest]

The difference in Florida's 450PPM tapwater mainly calcium, and using R/O water in soil grows astounds amazesand flippin freaks me out!I did OK for 5 years with this tapwater,all the while looking at my dogs bowl and wondering when I'm gonna get smart.I've known R/O is necessary in hydro,not so much in soil.Well I'm teliing everyone it makes a difference you wont believe,your plants will be falling all over themselves with trichweight at 40 days..