volume

I have a DS920+. Installed 2 x 12TB wd’s. Then I decided to add another. All accounted for after 3 days of whatever the system was doing. The Storage Pool shows 21.8 TB, but Volume 1 (the only volume ) still shows 10.5GB. So now I have 3 bays filled, but still only 10.5GB is showing in the pool...

I've setup MailCow on my DS718+ by running it in a seperate Ubuntu VM. MailCow stores all its data, like emails and databases in Docker volumes. So this is apparently saved in /var/lib/docker/volumes . These Docker volumes look like simple folders to me.. For backup purposes I wonder if it...