Black Ruby Barb

Pethia nigrofasciata

A fairly high-bodied barb with three broad bars and a reddish head. Strains differ in relative color, and a given fish will change color with mood and condition. A reddish head and a grayish body are the base coloration, but fish in top condition positively glow with red and iridescent black coloration.

This colorful barb has been a favorite for decades. It can even be maintained in an unheated aquarium at normal room temperatures. It is very important to keep these fish in groups. Although they do not school tightly most of the time, they love to play and spar with each other, and they will be stressed without conspecific tankmates. This is a fish that typically appears washed-out and drab in a dealer’s tank but will blossom into a gorgeous gem once settled in. Spawning males positively glow. They lose out compared to barbs that are much more colorful on display at the store, but those hobbyists who take them home will be well rewarded.

https://www.tfhmagazine.com/articles/freshwater/puntius-nigrofasciatus