Brown Pencilfish

About

The brown pencilfish (Nannostomus beckfordi) is the type species of its genus and one of the more adaptable members of the pencilfish group, making it a solid entry point for hobbyists new to keeping these slender South American characids. It's native to a broad sweep of lowland tropical waters, from the rivers of Guyana south through the Amazon basin all the way to the Rio Negro, where it frequents slow-moving streams and swampy areas rather than fast-flowing main channels. Coloration varies noticeably across its range. The form most commonly seen in the hobby shows a dark brown body with a bold lateral stripe extending into the central caudal-fin rays, red accents at the tail base, and ventral fins tipped with pale blue or white. Like its relatives, it adopts a cryptic pattern of vertical bars at night, which can alarm new keepers seeing it for the first time in the morning. This is completely normal and appears to be a hardwired response the fish cannot override. It's a peaceful species but does best with similarly calm, comparably sized tankmates rather than boisterous or much larger fish. Keeping a group of ten or more brings out bolder behavior and distributes any minor squabbling between males. It also works well as a dither fish alongside Apistogramma and other dwarf cichlids.