not sure i am clear on what you are trying to do ? One disk per raid group (type hot spare)  Note  A   thin LUN cannot be a Hot Spare. A hot spare is single disk that serves as a temporary replacement for   a failed disk in a RAID 6, 5, 3, 1, or 1/0 RAID group. Data from the failed   disk is reconstructed automatically on the hot spare from the parity or   mirrored data on the working disks in the LUN, so the data on the LUN   is always accessible. Disk that cannot be Hot Spares  1 In the Storage tree, right-click the icon for the storage system, and then click Storage Pool Options > Create   Storage Pool. -or- In the Storage tree, expand the icon for the storage system, right-click the RAID Groups   icon, and then click Create RAID Group. 2 In the Storage Pool dialog box, under Storage   Pool Parameters a Select the RAID Group storage pool type. b Assign a storage pool ID -  the   default value is the smallest available ID for the currently selected   storage system. You can assign a different ID from the Storage   Pool ID list. c Assign a name to the storage pool - the software assigns   name (RAID Goup x) that is not editable. d Assign the Hot Spare RAID type to the storage pool. e When you select a RAID type, the software automatically populates   Number   of Disks with one disk.. Alternatively, you can select a different   disk. 3 If you want to choose the disks yourself, under Disks, select Manual. a Click the Select button to open the Disk Selection dialog box. The software displays a list of valid disks for the selected   RAID type. b In Available Disks, select the disk and then click the   right arrow. The disk moves from Available   Disks into Selected Disks. c Click OK to return   to the Create Storage Pool dialog box. 4 To set advanced properties for  the    RAID group,   do one of the following: a You can decide to automatically destroy the RAID group   after the last LUN is destroyed, and you can set the priority  (Low,   Medium, or High) for expanding and defragmenting the RAID group. 5 Click Apply to   create the hot spare and then click Cancel to close the dialog box.
I have a CX3-40f with nine DAEs, 7 FC and 2 SATA.  The hot spares (so far, inherited from my predecessor) are singe drives in RAID groups with high numbers.  My question is:  Does it make sense to just use one hot-spare RAID group with all the spares (146G FC,300G FC and 1TB SATA), one RAID group for each type of drive, or one RAID group for each individyal drive?  Seems like a lot of RAID groups the way it was set up.  If there is no functionality limitation, my preference would be to put all theh hot spares into a single RAID group and then bind each drive as a separate hot-spare LUN.  Thanks in advace for nay input. 
Hot Spare best practice: one drive per RAID group or many?