Hi Phritz, I use this http://www.continuous-ink-systems.co.uk/AB-Refillable-Printer-Cartridges/c63/index.html?osCsid=ec6f09380d7e61f8e9e1f1a0fc4aef47 I don't know whether refillable cartridges are available for the P50. Claria are not the densest of inks for negatives but they work well for gum and iron processes, I don't use pictorica either - agfa works fine for me. Davidh