Ro water PH question

Re-read John Dee's post again and slow down.

If you start with the wrong conclusion you will go in 100 directions none of which will help fix issues you likely dont have.

Waiting for someone to provide logic how your measurement of 5.0 is valid is searching for the answer you want...vs the truth, which is you measured the ph wrong. It is 7, or real close.

I say this knowing i did too. Ive measured 6. And 8. Same water. Then i got a real meter, tested the water with both meters, with drops and every possible way to prove to myself that the problem was with <me> and how I use the equipment. And that some equipment is trash. AND that RO water or most purified is 7 0.

It was on this site, likely from Renfro, that I learned it should be 7.0. Start there. Until you can measure close to 7 its you and your equipment.

My 2c.

ComfortCreator said:

AND that RO water or most purified is 7 0.

Click to expand...

In actuality truly pure water has no pH at all until something is added to it to give it a pH. This is why pH meters can't really read pure water as they are made to measure 'potential Hydrogen'. When water is pure it's potential Hydrogen is 0.0 and if your meter said 0.0 you'd think it was super acidic and be tossing a whole bottle of pH Up in there to fix it.

pH is a very complex subject and not as simple as most people think it is.

ComfortCreator said:

Re-read John Dee's post again and slow down.

If you start with the wrong conclusion you will go in 100 directions none of which will help fix issues you likely dont have.

Waiting for someone to provide logic how your measurement of 5.0 is valid is searching for the answer you want...vs the truth, which is you measured the ph wrong. It is 7, or real close.

I say this knowing i did too. Ive measured 6. And 8. Same water. Then i got a real meter, tested the water with both meters, with drops and every possible way to prove to myself that the problem was with <me> and how I use the equipment. And that some equipment is trash. AND that RO water or most purified is 7 0.

It was on this site, likely from Renfro, that I learned it should be 7.0. Start there. Until you can measure close to 7 its you and your equipment.

My 2c.

Click to expand...

Almost, but not quite. The pH of pure water is considered "neutral" because the autoprotolysis of water can go either way very easily.
Its why adding an acid (pH down) decreases the pH much faster than adding it to a nute solution. So when pure water is left out in the air, the pH drops because its absorbing Co2.
The OPs pH measurement is likely accurate.
"Carbon dioxide reacts with water to form carbonic acid, which dissociates in water to hydronium and bicarbonate anion. This increases the concentration of H+ in solution, reducing the pH"

Edited-
Source cited for anyone that wants to brush up on their chemistry or dive down some rabbit holes. (I rec a little first though)
: http://ion.chem.usu.edu/~sbialkow/Classes/3650/Carbonate/Carbonic Acid.html