In the most recent versions of Pokémon Pelipper naturally learns Hydro Pump at level 58. However in the versions Pelipper was introduced in, Ruby and Sapphire, it will learn Hydro Pump at level 61 instead.
Azumarill learn Hydro Pump at level 57.
Swampert does not learn Hydro Pump.
blastoise learns hydro pump at level 44
Samurott learns Hydro Pump at level 62.
Empoleon Learns Hydro Pump At level 59/ 99Lloyd99
Azumarill learn Hydro Pump at level 57.
At level 40, Kingdra is suposed to learn Hydro Pump.
Swampert does not learn Hydro Pump.
Seadra learns hydro pump at level 40.
Croconaw learns Hydro Pump at level 51.
Milotic learns Hydro Pump at Level 40.
blastoise learns hydro pump at level 44
Samurott learns Hydro Pump at level 62.
Empoleon Learns Hydro Pump At level 59/ 99Lloyd99
Marshtomp is an evolved form of Mudkip, who learns hydro pump at level 42.
blastoise learns hydro pump at 63
It learns Hydro Pump at level 48.