The small fish with a red and black line from head to tail is a red zebrafish. The whole body is bright red, with red and black stripes on the sides from head to tail. It is very ornamental. The red zebrafish is a freshwater aquarium ornamental fish. It is native to Asia. It is about 4 cm (1.5 inches) long and has red stripes. The red zebra The fish has a lively and gentle temperament and can be kept alone or mixed with other small fish. It is one of the most popular tropical fish for people to keep.