By asking those people who sit in the house
The Super Rod is the only Rod that you can use to encounter Feebas in Emerald.
supe rod
FeebasUse a Super Rod.
A fisherman in dewford town will give you an old rod.
The super rod is received in mossdeep city.
there's no ultra rod there's only a old rod,good rod, & super rod..veronica
At Dewford town
tentacool and magikarp ... As you can also catch goldeen on emerald
you use the good rod in a river or somewhere :/
You have to fish with a super rod.
In mossdeep city there is a fisherman in a house that if spoken to will give you the super rod.
The super rod in pokemon ruby, sapphire and emerald is in mossdeep city.