Black Nerite snails, often called Black Racer Nerite snails, are a popular choice for aquariums due to their striking appearance and algae-eating abilities. They are known for their smooth, jet-black or dark brown shells, which provide a nice contrast in planted tanks and aquascapes. These snails are relatively small, typically reaching about 1 inch in diameter, and are highly active in their search for algae to graze on.