The Black Ruby Barb (Barbus nigrofasciatus) is a tropical fish belonging to the Barb family (Cyprinidae). Originating from Sri Lanka in forested streams from the Kelani basin to the Nilwala basin, they are found in streams on hills around 1000 ft (300 m) in elevation.

The Black Ruby Barb (Barbus nigrofasciatus) is a tropical fish belonging to the Barb family (Cyprinidae). Originating from Sri Lanka in forested streams from the Kelani basin to the Nilwala basin, they are found in streams on hills around 1000 ft (300 m) in elevation.

This fish is fairly common in the fish keeping hobby. The fish will grow to a maximum length of 2 - 3 inches (6.0 - 6.7 centimeters) with the female being slightly longer than the male.

Black Ruby Barbs natively live in a tropical climate among cool, shady forested streams with either gravel or sand substrates. Their diet mainly consists of algae and plant matter. They prefer water with a 6.0 - 6.5 pH, a water hardness of 5.0 - 12.0 dGH, and a temperature range of 72-79 F (22-26 C).

The young fish has a dark silver body with black vertical stripes. The silver body turns into a dark ruby red color in mature, breeding males. An egg-scatterer, the fish spawn more than 100 eggs in shallow water among the plants. The eggs hatch in 1 to 2 days and then will be free-swimming after 24 hours. The fish are successfully bred in captivity for the aquarium hobby.