Goldfish

The Goldfish is an fish that can be found in the river. It appears all year, all day. When selling it to Re-Tail, the player will earn 1,300 Bells.

Location
The Goldfish is found in the river.

The Museum
The Goldfish can be donated to the museum. Upon doing so, the following text is given by Blathers:

"These are aquarium fish that came about by selectively breeding types of crucian carp. It took hundreds of years to get the long tail fin and beautiful color of the current breed. Even red goldfish are black when they are young and still retain some other vestiges of the crucian carp. They turn red as they grow, thus gaining their much more commonly known look."

Quote
Upon catching the fish, the player will say the following:

"I caught a goldfish! It's worth its weight in gold!"