Systems and methods for tuning Key (K) black ink printed by a production printer. In one embodiment, an ink tuning system is implemented in a printing system. The printing system includes a production printer that is operable to print color ink onto a continuous-form medium, and includes a radiant dryer that is operable to dry the ink that is applied to the medium. The ink tuning system identifies areas of K black ink designated for printing on the medium by the production printer, and applies a liquid agent to the areas of K black ink to increase the liquid mass of the K black ink before the medium enters the radiant dryer.