Fathead minnow, also known as fathead or tuffy, is a species of temperate freshwater fish belonging to the genus Pimephales of the cyprinid family. The natural geographic range extends throughout much of North America, from central Canada south along the Rockies to Texas, and east to Virginia and the Northeastern United States. This minnow has also been introduced to many other areas via bait bucket releases. Its golden, or xanthic, strain, known as the rosy-red minnow, is a very common feeder fish sold in the United States and Canada. This fish is best known for producing Schreckstoff.

Feeder fish is the common name for certain types of small, inexpensive fish commonly fed as live food to other captive animals such as predatory fishes or carnivorous aquarium fish, turtles, crocodilians and other piscivores that naturally hunt in fresh, brackish or salt water ecosystems.