The real issue is that over time a meter may either become defective, have corrupted tips or fall out of meter tolerance, requiring recalibration. How would you know? Well, the smart and easy way to know is to periodically grab up the strips and do a test, attempting to see if the meter is still within your needful tolerance. You could do basic tap water (likely somewhere around 8, in most places), then drop in 10 drops of down and check a more acidic measurement (likely down in the 5 range). If the meter follows the test strips, put the strips up for another month, and proceed.
you are absolutely correct, and the pH meter shows a very unstable and unbelievable result in measuring low TDS deionized water, where the pH strip at least gives me a perfect range of results.
The real issue is that over time a meter may either become defective, have corrupted tips or fall out of meter tolerance, requiring recalibration. How would you know? Well, the smart and easy way to know is to periodically grab up the strips and do a test, attempting to see if the meter is still within your needful tolerance. You could do basic tap water (likely somewhere around 8, in most places), then drop in 10 drops of down and check a more acidic measurement (likely down in the 5 range). If the meter follows the test strips, put the strips up for another month, and proceed.
you are absolutely correct, and the pH meter shows a very unstable and unbelievable result in measuring low TDS deionized water, where the pH strip at least gives me a perfect range of results.