Add these lines to your .Xdefaults:
Xcursor.size: 22
Xcursor.theme: Grounation
!Xcursor.theme: Grounation-left
!Xcursor.theme: handhelds
!Xcursor.theme: jimmac
!Xcursor.theme: pCircle-24
!Xcursor.theme: pCircle-32
!Xcursor.theme: pDebian-24
!Xcursor.theme: pDebian-32
!Xcursor.theme: pSlackware-24
!Xcursor.theme: pSlackware-32
!Xcursor.theme: pSuse-24
!Xcursor.theme: pSuse-32
!Xcursor.theme: pTux-24
!Xcursor.theme: pTux-32
!Xcursor.theme: pUbuntu-24
!Xcursor.theme: pUbuntu-32
!Xcursor.theme: redglass
!Xcursor.theme: whiteglass
And use the ! for a commentsign. So the line without an ! in front
of it will be used.
