Catching fish is a good way to make money when you first start your life in Mineral Town. You might not have any animals to care for yet, but your waterways are full of fish to sell. Before you can try your luck at angling, you'll need a fishing pole!
Your first fishing pole will come from Zack, the shipper who lives with Mr.Won on Mineral Beach. If you visit him between the hours of 11am and 4pm, he will give you an old fishing pole that belong to his friend Greg. Greg moved out of Mineral Town and eventually ended up with his own television show that airs in Forgotten Valley (from A Wonderful Life for Gamecube).
There are many different waterways you can find fish in. You can go to Mineral Beach and fish in the Sea, or cast your line along the Down Stream area that flows from your farm and on past Barley's Ranch. You can also catch fish in the Harvest Goddess' Pond next to the Spring Mine, in the Lake where Kappa lives on Mother's Hill, and a little portion of Up Stream area between Kappa's Lake and the bridge that leads to the summit of the hill. Each of the 5 areas will have different fish to catch. The fish stocks will also change depending on the season.
All fish names and locations
To use your fishing pole, walk up to your chosen water area, equip it, and then press the B Button. Your line will cast out and wait in the water for a bite. When a fish nibbles on your line, you will see a ! above your head. That's when you press the B Button again to reel in your line! If you're skilled you'll pull up a fish. If not, just try again.
You may find that your first fishing pole doesn't catch very large fish. If you want a better one, you'll need to talk to Saibara the Blacksmith. If you find the appropriate ores in the Spring Mine, the Blacksmith will upgrade your fishing pole so you can catch larger fish. When you get the Mythril Fishing Pole you can catch a Power Berry and a Cooking Recipe. You can also find the Cursed Fishing Pole in the Winter Mine. Once you get it blessed by using it 255 times, you can catch the River King fish, Fish Fossils, and Pirate Treasures. If you go for the ultimate Mythic Fishing Pole than it will be easier for you to catch Fossils and Treasures to sell.
All the fish you catch will appear in your Farm Memo. You can see how many of a particular fish species you've caught, and even the largest size. Each time you catch a new species of fish you'll earn 5 points towards your Fishing Degree. For every 10cm over the size of your previous largest fish of that species, you'll earn 1 point. If you don't feel like selling your catch, you can throw the fish into the watering pond on your farm. You can only keep 100 fish in the pond and they don't grow in size.