The one thing strips do well is chlorine. Â With the Taylor kit, I don't have any issues as long as the free chlorine reading is under 3ppm, which it is almost always. Â Greater than three, its hard to read. Â I use the same method as Vinny to read combined chlorine. Â Shock time is when CC reaches .2 ppm. Â Try measuring that with the 2005 kit. Â With free chlorine at zero, any hint of pink while measuring total chlorine means its time to shock.