CLR on the outside of a copper pipe

My dad is dealing with an issue, looking for some advice and information.

He noticed that the copper pipe that brings the water into the house needed to be cleaned, so he used CLR. He realized afterwards the mistake. His water is testing high for copper (he was told safe level is max 1.2, he’s at a 3). What are his options? He’s under the impression that he needs to replace all the piping in his house, the hot water tank, and all his taps. Is it that bad?