One of the most common freshwater fish in the aquarium hobby today, and quite often the most unusual, is the Black Molly. Unlike the other types of Molly fish available in the fish keeping hobby, the Black Molly gets the majority of it’s traits as a result of captive breeding, and you would struggle to find one in the wild.
Almost all black mollies will be born with a serious case of melanism, which is a skin condition opposite to albinism (the lack of color pigmentation). While the majority of Black Molly fish are completely black, they can sometimes be found with a streak of yellow which runs down the dorsal fin, or a slightly silvery color on the flanks.
Black Mollies are relatively small in size, with the males growing to a maximum of 3 inches, and the females often growing a couple of inches larger. Their lifespan will completely depend on how well they are cared for, but in the perfect scenario, Black Molly fish can live up to 5 years in captivity.