Maiora pens take a wide variety of fountain pen, ballpoint and rollerball refills. Maiora fountain pens fit any brand of standard international-sized ink cartridges. Colorado Pen and Private Reserve offer a wide range of ink colors in these cartridges. You may opt to use the ink converter that came with your Maiora fountain pen. Then you can choose from any brand of bottled ink, including the huge Colorado Pen bottle, specially formulated to clean as you write.