You have to get a Super Rod and fish for it.
Use a good rod where you can find horsea use your pokedex if you seen one already.
And on leafgreen, and any other pokemon game, horsea evolves at level 40. Seadra evolves if you make it hold a dragon scale and than trade.
Simple find a good rod from a fishing guru and go to the shore of island 6 and use it until you get horsea. -PokemonAnswerMaster-
try to catch horsea this Pokemon hold a dragonscale sometime but you only have 5-10% I hope it help you^^
to catch a horsea one must sail through water and if you've seen one just go to your pokedex and check where it is most foundBY: DHARMVIR123
Horsea evolves into Seadra at level 32 and evolves again into Kingdra if you trade Seadra while its holding a Dragon ScalesIt evolves at level 32
You don't need a Evolution Stone, you need to simply level it up to 32.
HOW GET A HORSEA ON POKEMONINDIGO.COM
Horsea is a Kanto region pokemon.
You can't get horsea in xd.
you get horsea on route 226
you have to go to pacifidlog town and surf then you'll run into a horsea and that's how you get a horsea.