blastoise learns it at lv 68 not sure if squrtile can learn hydro pump hope this helps.
No he does not. The only way to get a Swampert to have Hydro Pump is to train your Mudkip to level 42 without evolving it. Then he will learn Hydro Pump, and then you can evolve him into a Swampert that will have Hydro Pump. (Emerald/Ruby/Sapphire)
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.
Milotic learns Hydro Pump at Level 40.
Croconaw learns Hydro Pump at level 51.
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.
first make squirtle level 16 then it should evolve into wartortle then make wartortle level 36 then it should evolve into blastoise and make blastoise level up and it should say blastoise wants to learn the move hydro pump but blastoise already knows 4 moves should a move be deleated and just say yes and deleat your weakest move