Nannostomus trifasciatus, the three lined pencilfish, is a small but beautiful aquarium fish native to the Rio Negro, and one of Project Piabas featured fishes. Three lined pencilfish reach a maximum size of 1.5 inches and have three striking bold black lines running down the length of their bodies. Their small size and relatively peaceful nature makes them perfect candidates for smaller biotope aquariums or larger community tanks with smaller fish. They do well in combination with more peaceful small tetras such as cardinal and rummynose tetras or with cryptic loricarid catfishes, but they can be freaked out by larger or more active and aggressive fishes. They thrive in blackwater tanks with leaflitter, and in planted tanks where they can feel as though they have comfortable hiding places to dart into. They adapt readily to flake foods and do best when also offered brine shrimp or some other small protein source such as finely chopped bloodworms or blackworms.
Photo credit Tom Christoffersen