Weeened off pool products.

[waterbear]

And aren't most of the "computer tests" simply a printout based on inputs derived from traditional forms of testing, which may not be as accurate (oto) and based on subjectivity?

Most are and are only as accurate at the info inputted into the computer.
Some are based on a scanner and test strips (ALEX by Bioguard is an example). These are very inaccurate, IMHO.
Then there are colorimeters that are connected to the computer. We have one of these at work (LaMotte Waterlink Express) that I have cross checked against my own testing at home with my pool and spa on a regular basis and have found it to be very close or the same as the readings I get with Ben's kit and my Taylor kit. Then again, there is the possiblility of operator error with ANY kind of testing or not knowing the ranges that can accurately be tested or interferances that occur (such as high sanitizer levels affecting pH and TA readings or metals affecting CH readings!)

[CanuckPool]

would it be good to average your reading with the pool store?

[waterbear]

In a word....NO...I would trust my own readings!

[PatL34]

For a SWCG use muriatic acid rather than pH Minus. Muriatic acid is part of the SWCG process, ph Minus is not.

Pat