You can choose Piplup, a Water type starter pokemon at the beginning of the game, or catch a Wild Bidoof, Bibarel, Buizel or Floatzel, all of which are Water Type Pokemon
You can get a Seel in Pokemon Pearl by finding it in the water on route 226.
Water and grass
blastoise is the best
You cant
With a water type pokemon.
You cant
nearly all water Pokemon
fishing or surfing
you have to teach it to a water Pokemon and then go to Pokemon, select the Pokemon you taught it to and you can dive.
He has a Gyarados, Quagsire, and a Floatzel
It's the water type, Milotic.
gyrados