Lignite Carbon

If you have lignite carbon tank(s) in line do you monitor them in any other way besides delta pressure? While that is all that we have been instructed to do by our vendor technical service,  I wonder if pH,  free chlorine, or chloramines shouldn't be monitored daily or weekly.  We have exchangeable, so the vendors assumption is it will do it's job removing organics to assist the carbons with chloramine removal, and be swapped out before there is a failure to do so.   Would love to learn more about this from anyone willing to offer up some info or resources for info. - thanks!