Expanding R810 Storage

Hello all,

This is the first time posting to the Forums on delltechcenter.com, so my apologies in advance if this question is not posted to the correct group.

My question.

I have a PE r810 server with a PERC H700 integrated storage controller.  I have filled all available HDD slot with  6 x 130GB SAS HD's.  These drives are configured in a RAID 6 configuration plus one hotspare.  My question is:  I'm running low on the disk space, what's the best way to increase the storage capacity without bring the production server offline? The server is running Windows 2008 R2 with Oracle database installed. It's a mission critical database being accessed 24/7. I know the PERC H700 support hot swap, is it possible to buy a larger HDD and swap it out one by one (let it rebuilding all the HDD). Anyone have any experience on this type of expansion? Thank you.