What kind of media? Walnut shells, aluminum oxide, glass, plastic beads, etc etc ?
All are types of media, sand is a general term that get tossed around but I don't know anyone that actually shoots sand at parts. Media is a term used to describe many different abrasive meterials used to media blast
I use mostly aluminum oxide which comes in more then a dozen different grits
You need to be more specific as "media" could be many different things
give it to somebody that understands the project, use the wrong media/ pressure/ idiot running the nozzle, and you can warp metal parts.