Yeah. That's pretty much what I expected.

At best, your ACTUAL chlorine reading is 7 ppm plus or minus 1. All those extra digits in you answers are bogus -- your test method can't distinguish 7 ppm from 6 ppm, much less 6.61 from 6.71 ppm.

But I'm not sure it's even that accurate. Please get a cheap OTO / phenol red kit. The OTO kit is not super accurate, but it is reliable. And see if you have have your CYA tested. There is NO method available to homeowners that can distinguish 60 ppm from 62 ppm. Most can't distinguish 60 ppm from 70 ppm.

But, assuming your do have 7 ppm Cl + 60 ppm CYA, your chlorine readings are reasonable and don't need 'fixing'.

Ben