OK I packed it again, and it's still 25 gigs. It hasn't gone down much.
Just making sure I'm packing correctly... I go to /Control_Panel/Database/main/manage_main and then where it says "removing previous revisions of objects that are older than __ days." I put 0 and then I hit pack. If there's another step to it I'm not aware, please let me know.
Other than that, I don't really understand why it's not getting rid of that chunk of space. I'm tempted to just delete the files in blobstorage itself, but worried it might break something.