pool info: 26,000 ingound vinyl, ph 7.3, cl 10.0 , cc 0.0, cya 75, alk 150, been using BBB method. plan to go swimming this weekend. decided to shock it 2 days ago with a goal of 30 ppm chlorine. i added bleach and tested and got 23ppm cl. I then added 5 more 3/4 gal bottles of 6% bleach as each bottle usually gives me about 2 ppm and retested and only got 26 ppm. i added 4 more bottles , waited 2 hours and retested and got 26ppm again. test water never really got clear when it changed from red but became kinda a pewter color. using ben's 233 kit with one year old dpd powder and drops. any idea why i couldn't get a higher cl reading ?