remove existing RAID setup

I purchased a 12 core MacPro which was setup with 4 new 3T seagate drives as a 12T RAID. Supplier was more video based and I'm a 3D modeler.

I stated copying over files from another Synology RAID system I have but then decided I would rather use your software for a RAID 1 4 disk repeat setup. I have 11 years of major models to protect.

The 12 core is running off a SSDHD drive under OS 10.11.2 and I assume that the supplier used the Mac Disk Utilities to set up the RAID.

I do not see a way to remove the existing RAID and thought I would ask here before I proceed. I have SoftRAID Lite downloaded and installed but have not opened yet. I have seen a lot of comments about 10.11.2... the 2 update being the problem.

I'm 68, retired and and would appreciate suggestions or insights.

Thanks