TbFeCo magneto-optical single layer disks with different compositions have been investigated for recording of small size domains. Using a 830 nm wavelength laser, circular shaped domains with a diameter of 0.25 μm diameter could successfully be written. A low writing stability, dependent on the applied field, was found when recording domains smaller than 0.5 μm on a transition metal rich disk. On the contrary, a high writing stability was achieved on a disk with a highly rare earth rich composition. On this disk two 0.25 μm domains could succesfully be written as close as 0.1 μm to each other. It was also possible to use this single layer TbFeCo disk for recording of domains with widths of 0.1 μm.