When using hard drives in this NAS model, you can generally also install WD Red or Seagate hard drives, not just Synology's own hard drives. However, Synology has introduced a stricter compatibility check for the 2025 NAS models, in which only officially certified drives are fully supported. Unverified third-party hard drives can trigger warning messages and are not permitted for storage expansions. While Synology is working with manufacturers such as WD and Seagate to certify additional drives, full compatibility is currently only guaranteed for selected models.