Changed the water this weekend for the first time. After filling the tub, checked the water with the test strip. It was perfect out of the tap. Free chlorine 0.5, ph 7.4 Al 120.
Added a bottle of Spa Sentry per dealer recommendation to lock it in, Ph changed to 6.8, Alk 180.
This is the second time this has happened. What am I doing wrong?
Using dichlor, ozone, N2