(like) water off a duck's back

US /ˈwɔtər ɔf ə dʌks bæk/
UK /ˈwɔtər ɔf ə dʌks bæk/
"(like) water off a duck's back" picture
1.

come acqua fresca, non fare effetto

criticism or negative comments that have no effect on someone

:
He tried to insult her, but it was like water off a duck's back.
Ha provato a insultarla, ma è stato come acqua fresca.
Criticism rolls off him like water off a duck's back.
Le critiche gli scivolano addosso come acqua fresca.