A system for reducing ink color mixing effects in a printer is provided having a printhead having multiple ink color channels mounted to a housing of the printer at a first level, and a plurality of ink supply cartridges mounted to the printer housing so as to be fluidically connected to the printhead and stacked in an array having a plurality of rows defining a plurality of levels which are lower than the first level. The plurality of ink supply cartridges include at least one black ink supply cartridge which supplies black colored ink to a black ink color channel of the printhead. The black ink supply cartridge is disposed at the lowest level defined by the array.