Left over space from a RAID 5 setup - can it be used?

[Combat squirrel]

As title, using freeNAS with 2x2TB and 2x1.5TB drives, obviously leaves me with a TB free.......can this be mounted as a normal JBOD partition from the left over space ?

 

[Combat squirrel]

Can you not create another array, either 500GB RAID1, or 1TB RAID0 in Freenas?

That's what I was hoping.......can freeNAS do that ?