Pokemon---

Actually, you need to specify which gameboy version or other Pokemon online games that you want to find Water Pokemon. Basically, you can find Water Pokemon in wherever places that have water. You can use Old Rod, Good Rod and Super Rod to catch Water Pokemon. You may lower down their HP by using grass or electris attacks, and you can make them fall asleep or paralysed so that it will be easier for you to catch. The most important, you must buy enough Pokeballs!

in the river or sea

Jump into the water and use your hand to find.

釣魚或是游水

I do not NO!