I can update my Pool Size we are using MFSYS25 with MFS5520VI Compute Module Firmware version is Current Build Version: 6.5.100.20100630.21247
I fallow the below mention Prosess
i) First we put a 600 GB HDD as a global hotspare and replace the all 146 gb HDD one by one after rebiled compleated in each drive every time one 600 gb HDD are hot spare after replace the all HDD & rebuilding compleated our pool space not update
ii) After it I Make HDD force offline and put a Fresh 600 GB HDD on that place and start Manually Rebuilding of raid but not hotspare diffend that time , after doning same Prosses in all HDD i am able to Access the Increassed space