Standing water pH changing?

[F46531C4]

I've been having what I am pretty sure are pH issues from the get-go. at first i didnt have a pH meter, and not surprisingly, when I finally got a digital meter (Oakton), the pH of my tapwater tested near 8.0.

so now after letting the water sit for a couple hours, i've been using ph down to get it to 6.5.

after a couple days, I decided to re-test my sitting water, only to find it back up at 7.5. i figured the meter was out of calibration, so i bought some cal fluid and tested it -the meter tests perfectly. there's not nutes, just tap water.

question: is this normal, or is my meter (or something else) screwed?

old plus new plants are all suffering.

 

[BigDog]

If I drop the pH on my water using pH down and than wait a day or so, the ph will rise.

 

[HotshotShorty]

MY water goes from 7 to 8 in a couple days just sitting out.
any clues?

 

[Fuzzy Duck]

Mmm interesting question...

Tap water a Ph value of 8 is pretty hard water & more than likely coming from an area of limestone/chalk bed rock.


Might be an element/compound/mineral in hard water which reacts with PH down (nitric acid or phosphoric acid) negating acid effect over time ?


Prehaps the PH down just evourates more quickly when mixed with nutrient enriched water and slowly disperse's/evapourates over time restoring natural PH of water source back to original PH ?

 

[oldman60]

Strange problem. Normally water when exposed to air reacts with the CO2 forming carbonic acid which
lowers the ph slightly. I've noticed a slight drop in my RO water after it has sit in the barrel a while.

What are you using to adjust the ph? I recently switched from GH liquid to GH dry mix and the dry is woking
much better for me. It seems much stronger and keeps the ph in range longer than the liquid I was using.

 

[WizHigh]

Yea I would go with a stronger PH down. Like oldman60 said I switched to dry and it is a lot better at controlling PH and it last a lot longer also.

Which PH line are you using now? Go with GH PH dry

 

[HotshotShorty]

Greetings,
Up here in Oregon, this area was a conglomeration of other areas, all folded up and pushed east. Lots of gold mining history.
My water is from a well which is located at the bottom of a hill. The ph tests 7 with a drop liquid tester and then in a couple days it is at 8. I am planning on a 20 gallon water storage to bubble O2(air), so eventually I will know if that effects the ph. I had rather adjust the ph fewer times.

HotshotShorty

 

[HotshotShorty]

Here is documentation of standing water rising in PH

Out of the tap we have a 7:

After sitting 24 hrs in a watering can, the PH is now 8 :

I am wondering if this caused a nutrient lockout with my project?

 

[WizHigh]

Its probably after all the chlorine and crap (aerate) is out of it the PH rises. There's nothing wrong with that. Just as long as its PH to the right number before feeding your plants or running your hydro.

 

[HotshotShorty]

Sorry, I forgot to mention that it is well water- unfiltered.

 

[WizHigh]

When you leave water sitting out over night it kills most of the bad stuff in the water. So once that happens the PH will fluctuate. So if your PH rises a whole point over night all you have to do is PH Down it to around 5.0 & over night it will settle around 6.0-6.5

 

[Fuzzy Duck]

Well i was looking at some aquaponics stuff... ya know keeping fish & using the water to feed the plants with etc


Well there appears to be some water science related stuff to all this PH swings etc ya may want to look into this - Alkalinity KH: How well your water can resist (buffer) changes in pH. yup do a google search on that one


A lot of the info generated relates to aquairum (fish keeping) Ph level of the fish tanks, fish are bit sensitive to Ph change bad for their health !

As is Ph change in hydroponics aka water gardening.



I think theirs some thing to learn from these fish lovers & the matter of - Alkalinity KH: How well your water can resist (buffer) changes in pH.

Not sure how this all relates tho at present... but interesting reading.

 

[HotshotShorty]

That was a good resource idea.
in looking over what they were concerned about, They want a PH 8.2 or so.
However, one article addressed lowering the ph.
his idea was that it was not as simple as adding PH down.
Other things could be buffering it to keep it up.
His idea was to use a reverse osmosis system eliminate any buffering.
I have wondered if my ph rose after I watered the girls.

 

[Fuzzy Duck]

Aye was indeed interesting reading.

Original i was looking at aquaponics the art of keeping fish and using their waste by production through bacteria break down to create nutrients in the water to feed plants an ebb & flood system before getting side tracked with aquarium stuff...

The fish used in aquaponics generally live in between a PH range of PH 6 to PH 9.

Optimal plant growth is in the neutral PH range of PH 6 to PH 7.


So thats quite a fine balance to achieve in a micro eco system working in harmony with each other for optimal PH level for both fish & plants.

This is where buffering comes into play i believe ?

More on the lines of long term PH mangerment to prevent large swings in PH level whether water used for aquarium was from soft or hard water areas.


Mmm i'm gonna visit an aquarium shop 'n' question somebody

 

[HotshotShorty]

So my well water is PH 7.
Aerate it & it rises to PH 8.
PH down to PH6.3 (1 gram PH down/gal)
Aerate again--- PH rises back to PH 8.

Looks like I need a reverse osmosis system.

 

[WizHigh]

Theres nothing wrong with your PH fluctuating. All liquid will do so unless its around 4-5 gallons. The more water the steady the PH will be.

 

[HotshotShorty]

In this case, there was no fluctuate. It just went up.
As a result, there was nutrient lockout, -a near death experience.
So I PH down and then PH down again. (2 days).
This will all be a mute point with me, because I have bought a reverse osmosis system.
My well water, for whatever reason, becomes alkaline when exposed to air and appears to be buffered as the PH has to be lowered twice before it remains stable.