At 7 p.m. tonight, I added 4 gallons of 12.5%. One hour later I tested using the Taylor K-2006 and got FC of 7.5 and CC of 2.0. Was a bit surprised that FC was only 7.5. Will test again around 7 a.m. and see what has changed. Any thoughts about the pool store liquid only bringing me up to 7.5 FC?