NANFA-- pH kits / chemistry question

R. W. Wolff (
Thu, 19 Sep 2002 15:18:32 -0500

I have a very old pH kit that uses the drops of dark liquid. Two drops to a
vial and then it turns the color to indicate pH. My question is, how long
does this stuff last on the shelf? Does it give funny readings as it ages?
I ask because it seems senstive to high pH, running right off the chart if
its just above neutral.
Also, what test kits are most reliable. I don't care if they are harder to
use. I like the seeming percision of the drop test, but the dip paper strips
are so easy, and the tablets I have not tried. The electronic meters I have
tried seem to be worthless. They never worked right, and the calibration
solutions I do not rely on, especially if these chemicals also change
sitting on the shelf for any amount of time. Plus the warnings that they
are sensitive and you need to do this and that and the other thing to make
sure they are going to work right. With all those variables, I just don't
see them being reliably accurate. Maybe them 300 dollar ones are, but I am
not about to spend that to test pH or any other parameter.

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