like water off a ducks back

like water off a duck's back  {adv. phr.},  {informal}
Without changing your feelings or opinion; without effect.
Advice and correction roll off him like water off a duck's back.
Many people showed him they didn't like what he was doing, but their disapproval passed off him like water off a duck's back.
Categories: {adv. phr.} {informal}