Nibble fish

The Nibble Fish (ドクターフィッシュ, Dokutā fisshu) is a fish that was first introduced in. They can be found between 9 AM and 4 PM in the river from May to September.

In
After a nibble fish is donated, a sign in the museum will display information about this fish.

"The official name given to this warm-water-dwelling species of fish is "Garra rufa." They are omnivorous, as they both eat algae and scrape the skin off other fish. All you'd have to do to feed them is stick your hand in the tank; they would live off your dead skin. That's why they're called nibble fish. They exfoliate but don't have any teeth, so it doesn't hurt at all!"

In
Blathers has this to say about the nibble fish:

"Nibble fish are best known for their use in a certain...skin treatment. This treatment has been apparently been used for thousands of years. I have never...experienced said treatment...because they eat your dead skin with their little toothless mouths! Can you imagine anything so repellent?! Please don't ask me any follow-up questions. Hoo. "

When donated, the nibble fish is displayed in the small freshwater fish tank in the fish exhibit with the Betta.

Real-world information
Commonly known as doctor fish, Garra rufa are used in some methods of spa treatment, and have even been known to alleviate symptoms of psoriasis.