Just to elaborate, CC's are not something that is directly added to your pool. Think of CC's as spent FC. They are a byproduct, a leftover, of FC oxidizing organic material. A healthy, well balanced pool will have less than 0.5 ppm CC's. As Jezza noted, sunlight will remove CC's, this is why leaving a cover on can cause a high CC reading temporarily, as well as raising FC levels will eliminate organics in the water and reduce CC production.
Word of caution tho, do not try to use CC's as a measure of your FC effectiveness, i.e. "my pool is cloudy and I raised FC, but I am not generating any CC's so it must not be algae." Measurable CC may or may not be formed when FC kills something or it may simply be burning off by sunlight (UV) prior to sampling.
FC = Good, CC = Bad. Like your case with CC of 1.5, it is telling you that there is something in your water that your FC is fighting necessitating a SLAM - even when your water is otherwise clear!