Why is allocation less than capacity?

Seems I'm thwarted by this *(&^*#&^T%$ box every time I try to do something...

I've got a Pro 6 NAS that I bought with 6x1TB drives. I wanted to upgrade the capacity by installing 6x3TB drives. A call to tech support suggested the best way was to do a "factory reset", so of course, this is what I did/tried to do as follows:

1. From Frontview, I selected the "Factory Default" button. When the process started, I was prompted to make some inputs to configure the unit.

2. Before making the entries, and restarting, I removed and replaced all 6 1TB drives with WD Red 3 TB drives.

3. In Frontview, I selected the X-RAID2 option with tolerance for 2 disk failures, and hit the go button

4. The process began, but as I view the Frontview volume settings, it seems I will wind up with only a fraction of the available capacity because only 927 GB on each disk is "allocated" (see screenshot)

What is going on here?? Why am I not getting the entire 2,794 GB from each drive allocated?

Thanks!