Rev,
Are you sure you don't have those numbers reversed? pH=8 and Cl=21-32?
Even if you do, the pool store is incorrect.
This post points again to how important it is for everyone to have a decent test kit and understand what the results mean.
Rev, the process will work and I'm sure the pool store guy is a nice guy....but, he's misinformed.
Double check those numbers and get a complete set of test results....pH, Alk, FC, TC. That'll do more to help you get back on track than anything you put in your pool without testing.
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