Saltwater fish!

[Madreefer]

Your tank is not near ready. Any reputable store would never suggest what you were told. I wouldnt go back. Go get yourself some test kits and start doing alot of research. IME royal grammas are too aggressive and a 10g is too small for a pair of clowns. There's a fair amount of newbies that read alot and like to give advice. Most of it is wrong so try to take advice with those who have actual experience in the hobby.