I keep trying recalibrate my pH meter using my profilux and I keep getting a different reading from my Hanna checker. Not sure which is actually more acurate. At first I thought it was the reagents from GHL which I got used. At that time there was about a .3-.4 discrepancy. Now after recalibrating using lab grade solutions its off by a little more. I have the Milwaukee MA911B/2. It was recommeded to me and I got it brand new.
pH meter What am I doing wrong?
- Thread starter Aeb1419
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saltypepper
Active Member
Silly question but do you know the Hanna is right? Is it recently calibrated?
gbroadbridge
2500 Club Member
The Hanna cannot be calibrated. It can be tested against a reference to check it is functioning correctly.I do not. I didnt even know it can be calibrated.
Will look it up thanks
Its stated accuracy is +- 0.2pH
If you've calibrated the Profilux using pH 7 and 10 buffers or similar it is probably accurate to within the same range, so if the difference is less than 0.5 they're both correct.
It really doesn't matter, either reading is fine.
Thanks. I just worry because in the future I plan to dose and would like to know if my pH is going to high or not.
Plus im doubtful because I dont dose and Im confused if my pH is actually 8.4. I am doing nothing to achieve that. And the fact thats my actual goal for pH, worries me that it might not be accurate and I eithet dont dose thinking its correct, or dose to much and get close to 9.
Ph is notoriously hard to test with any accuracy, ph testers can cost thousands and the probes need replacing often, I have little faith that a hanna checker that costs $70 and can not be calibrated is going to be reliable.
Randy Holmes-Farley
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It is unusual to dose and have pH get high, unless you dose a lit at once.
