Which chart should a person use there is 2 of them one older is the new one better? It seems my FC should be higher with the new one. Or is either ok to use?
Acknowledgment: The original Chlorine/CYA "Best Guess" chart was developed by Ben Powell. Richard Falk (chem geek) has refined and expanded on that original to produce the Chlorine/CYA Chart by Chem Geek based on experiences with members on this forum and the old Pool Forum and conformation to chemical theory.