Freshwater rainbow fish are a colorful and popular species of fish that originate from Australia, Papua New Guinea, and nearby regions. They are known for their striking, iridescent colors that can range from blue and green to red and orange. They are peaceful fish that thrive in groups and make a great addition to a community aquarium. Rainbow fish prefer a well-planted tank with plenty of open swimming space. They are generally easy to care for and can tolerate a range of water conditions, though they prefer slightly alkaline water with a pH between 7.0 and 8.0. Their diet should consist of high-quality flake or pellet food supplemented with live or frozen foods such as brine shrimp or bloodworms. Overall, freshwater rainbow fish are a popular and attractive choice for aquarium enthusiasts.