Successfully complete the indicated task at the Fishing Pond in Mabe Village to unlock the corresponding bonus:
Fishing Pond Unlockables
Chamber Stone 1: Catch a Blue Ol’ Baron.
Chamber Stone 2: Catch a Blue Ol’ Baron 60 inches or better.
Fairy Bottle: Found in the bottom-left area of the Pond’s Floor. Hook it and reel it in to get it.
Heart Piece 1: Catch a Small Red Fish.
Heart Piece 2: Catch a Large Green Fish.
Heavyweight Lure: Catch a Blooper. Bloopers start appearing after Level 5.
Middleweight Lure: Catch a Large Green Fish.
Secret Seashell 1: Catch a Cheep Cheep. Cheep Cheeps start appearing after Level 4.
Secret Seashell 2: Catch a Blooper. Bloopers start appearing after Level 5.