An electrophotographic printing apparatus includes an image-forming member having a surface on which a latent electrostatic image can be formed and a developer for depositing a layer of ink onto the surface of the image-forming member. The ink includes charged ink particles and a carrier medium. A supply conduit is connectable to an ink tank for supplying ink to the developer. An exit conduit is connectable to the ink tank for delivering unused ink from the developer to the ink tank. The supply conduit, the developer and the exit conduit define a flow path. A separator is operable to separate the carrier medium from the ink particles. The separator is connectable to the flow path to receive unused ink and to reintroduce carrier medium extracted from the unused ink to the flow path.