pH meter questions

[headshake]

what's good everybody? i recently received a gift of a pH meter (thanks again M.P.!). the manual says to "stir gently and wait for a steady reading".

now when i just stick the meter in the water, it reads 7.25 but when i stir it drops to 7.01. i know the manual says stir, but is it common for the pH to read so differently?

thanks for the help!


-shake

headshake Reviewed by headshake on 10-24-2009. pH meter questions what's good everybody? i recently received a gift of a pH meter (thanks again M.P.!). the manual says to "stir gently and wait for a steady reading". now when i just stick the meter in the water, it reads 7.25 but when i stir it drops to 7.01. i know the manual says stir, but is it common for the pH to read so differently? thanks for the help! -shake Rating: 5

[disrupt86]

i wouldnt worry about it 2 much.chances are your catching pockets of disolved solids on your water .hmmm on the other hand i have noticed something weird.at my job we use 2 seperate constante ph probes. if we spin the water counter clock wise with the probe it makes the meter go nuts.my personal meter does the same thing u dont have a hannah red pen do u ?

[DreadedHermie]

Dunno if this is any help, but my little Milwaukee meter seems to remember the last thing I had it stuck in, to an extent. It seems like the probes may have an absorbent element of some kind. And Disrupt's right, .2 isn't much--I never trust a meter blindly in case it suddenly goes out of whack. I kinda plan for accuracy no better than +-.2, I guess. :hippy:

Hermie

[disrupt86]

Dunno if this is any help, but my little Milwaukee meter seems to remember the last thing I had it stuck in, to an extent. It seems like the probes may have an absorbent element of some kind. And Disrupt's right, .2 isn't much--I never trust a meter blindly in case it suddenly goes out of whack. I kinda plan for accuracy no better than +-.2, I guess. :hippy:

Hermie

whats happening when u get the exact same constant readings is your getting scale build up.all the stuff in your water will slowy start to scale over the glass lense and after it has dried it sticks,sooooooo the next time u go to check ph it gets wet and gives u inacurate readings.this is why it is a verry good idea to run hot water over your meter after every use. personally i use 2 methodes every time i test ph.my hanna and these ph paper strips i take from my work.i honestly think im just going to toss my digital meter cuz paper just doesnt lie "unless its a police report"

[Horsemanrocks]

"stir gently and wait for a steady reading".

The reason to stir is to remove whatever the old solution on the bulb wasâ?¦.and replace it with the new solution. Youâ??ll never let the meter â??settle inâ?� while stirring. Stir a while (15-20 sec) stop stirringâ?¦..let the meter settle inâ?¦.and viola your true Ph.

Thanks for all your contributions in the past.
Horsemanrocks.

[headshake]

thanks for all the help and input guys.

disrupt, it is a red hanna pen. it seems to work spot on otherwise and even stays calibrated just fine so far.


-shake

[tristan1986]

They also say too gently stir because air bubbles form on the electrodes when first placing in the water :thumbsup: