samurott's the best.
but i like all water types.
my sister likes ducklett because she thinks its cute.
Seismatoad, followed by Simipour, Samurott, Empoleon, Swampert, Blastoise, Feraligatr, Azumarill, Milotic, Octillery, Vaporeon, Kingdra, Starmie, Ludicolo, Carracosta, Kabutops, Keldeo, Manaphy and Phione,
Well Swampert is my favourite water type. (Can't argue with that)
I use to be a Water Type based trainer so I have a bit of a list of fav water types I would like to share.