Vampire Fish

About

The vampire fish (Hydrolycus armatus) is one of those species that grabs attention at the fish store as a juvenile and then quietly becomes someone else's problem a few years later. Native to the Amazon and Orinoco basins and river systems of Guyana, this is a large, open-water predator that reaches nearly three feet as an adult. It belongs to the dogtooth characins, a group defined by their oblique mouths and elongated canine teeth on the lower jaw. Teeth so pronounced they slot into dedicated openings in the upper jaw, letting the mouth close fully. The body is silvery with a slightly darker back, and the caudal and anal fins carry a distinctive black submarginal band with a white outer edge. A detail that separates it from related species in the genus. In the aquarium it is aggressive, particularly toward its own kind and anything that resembles it, so it's best kept alone or with large, bottom-dwelling tankmates. The honest truth is that this fish demands truly exceptional facilities: enormous tanks, serious filtration, and a long-term plan for an animal that can live for years. Juveniles are occasionally sold without that context being made clear, which is worth knowing before you fall for one.