IF it was mine I'de have it seperated from the others till you know it's going to be ok. Not seperate tank but behind a divider. I know if I was feeling what that ray is now I'de want to be left the hell alone.......
I felt the same way when I had a new ray take out an Armatus (that I busted my arse to break off live) in less than a week in my possesion. I still call him ol dirty (cause he's a friggin basturd for taking my favorite fish away)
Never pull out a stinger. They are barbed all the way from the tip to the bottom. On both sides. So it will rip in the flesh of the fish when you pull it out backwards. Works just like a fishhook.