How to properly allocate the disks for a raid?

Hey I'm having trouble rebuilding this Compellent Raid and wondering how I utilize 80% of each disk for my raid/storage.

It is showing as 0% and 0.01 allocated. I did just rebuild it so not sure if it will eventually allocate more of the drives? but I didnt see any options on how to specify this. If anyone has any step by step's that'd be highly appreciated.