Originally Posted by Pokemon Trainer Sarah
You have to fish in every tile of water on Route 119 until you find Feebas. It will appear in only 6 tiles of water on the route. It's best to use an Old Rod so you won't run into too many other Pokemon while searching, but you can catch it with any Rod. There are no tricks or hints, and no easier way to find it. Just be patient and you'll find it eventually.
Good luck. ^_^
right but try to catch a male and female so you can breed them if your planing on evolving him...i found that out the hard way