in grass close by water and in in water and while fishing
You can capture Feebas on Route 119 in Pokemon Ruby, this is dependant on the phrase in Dewford (that changes it's location) and is luck to find the correct tile that Feebas appears on when fishing.
every time you see it say got a nibble press a and soon you will hook a Pokemon
you go to the docks near jubilife city go back into the house talk to the fishermen he will give you a fishing rod
you just get a rod it doesnt matter what rod it is at the place where there are 2 gym leaders search around and a fisherman will give you one
In dewford Island and Mossdeep city forgot about good rod though..
if you want fishing pole in ruby you need to beat elite 4 then fly home and you mum will say that you dad called and want you to come to his gym fast then he say hes friend Pokemon is stuck in a cave then just go into the cave (don't know the name) and search around and you will see a Pokemon on the floor press A on it so it not so hard
in the somewhat tall grass. or when you are fishing with a fishing pole. or when you run into a Pokemon when surfing on water.
With a fishing rod that you can obtain in Dewford.
You can obtain Horsea by fishing on Routes 132, 133, and 134 in Pokemon Ruby.
just surf on the ocean..
magikarp
at jubilife or enterna city
you get it in the house on silence bridge
yes you do need a fishing pole to catch mitotic in Pokemon black but you cant catch that Pokemon you have to catch the first evolvation and then you train it until in evolve into a mitotic
go to the lake of rage
Heck if I know!! Haha