To keep things simple, I turned off all but one array (called "array_2") and rebooted the computer.
Under "Internal", Disk Utility lists "array_2 Media" in black as "Disk image internal physical disc", 23.94 TB, disk10
Under "External", Disk Utility lists the eight 2 TB hard drives as "array_2" (x 8) in gray as "Unknown ZFS Dataset".
Diskutil list gives the following output for the array:
/dev/disk1 (internal, virtual):
#: TYPE NAME SIZE IDENTIFIER
0: Apple_HFS Macintosh HD +999.0 GB disk1
Logical Volume on disk0s2
A241BF87-6E38-4FAD-A9B1-BD5059DDCA80
Unencrypted
/dev/disk2 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk2
1: EFI EFI 209.7 MB disk2s1
2: ZFS array_2 4.0 TB disk2s2
/dev/disk3 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk3
1: EFI EFI 209.7 MB disk3s1
2: ZFS array_2 4.0 TB disk3s2
/dev/disk4 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk4
1: EFI EFI 209.7 MB disk4s1
2: ZFS array_2 4.0 TB disk4s2
/dev/disk5 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk5
1: EFI EFI 209.7 MB disk5s1
2: ZFS array_2 4.0 TB disk5s2
/dev/disk6 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk6
1: EFI EFI 209.7 MB disk6s1
2: ZFS array_2 4.0 TB disk6s2
/dev/disk7 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk7
1: EFI EFI 209.7 MB disk7s1
2: ZFS array_2 4.0 TB disk7s2
/dev/disk8 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk8
1: EFI EFI 209.7 MB disk8s1
2: ZFS array_2 4.0 TB disk8s2
/dev/disk9 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *4.0 TB disk9
1: EFI EFI 209.7 MB disk9s1
2: ZFS array_2 4.0 TB disk9s2
/dev/disk10 (internal, virtual):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme +23.9 TB disk10