thats not that big though really
my last 2 were 2.5 but im sure there are people with alot bigger
why not see what the biggest is and what size ray it came from.
it is best to get them out because if you are moving anything in the tank and run into it they can hurt mine are very sharp and they are serrated down the sides.
it wont do as much damafge as the ray would do with it but traces of venom are lft behind sometimes i have one thats black all over so you need to handle with care although i dont think such a small amount would affect you to much but i could be wrong.
I boil mine after they come out of the tank but even then I am sure they make my skin tingle a little afterwards for a few hours....anyone else found this?