The Rummy Nose Tetra (Petitella spp.) is a popular, torpedo-shaped freshwater fish known for its bright red face and black-and-white striped tail. Typically reaching about 4–5 cm in size, these active schoolers live 5 to 6 years. They are highly social, requiring groups of at least 6–8 individuals to thrive, and often serve as water quality indicators, as their red noses fade when stressed.