The DS1823xs+ adds 24 more bays via two expansion units
Two eSATA ports support up to two DX1222 expansion units (12 bays each), and it has one PCIe 3.0 x8 slot for a 10GbE card or M.2 SSD adapter.
Two eSATA ports support up to two DX1222 expansion units (12 bays each), and it has one PCIe 3.0 x8 slot for a 10GbE card or M.2 SSD adapter.