Red Mouth Headstander

About

The red mouth headstander (Anostomus ternetzi) is one of two members of its genus that show up regularly in the hobby, and it's the more agreeable of the pair compared to its close relative Anostomus anostomus. Native to fast-moving stretches of the Orinoco, Amazon, and Araguaia river systems, as well as coastal rivers of the Guianas, this fish carries the classic anostomid body plan: moderately elongate, somewhat cylindrical, and patterned with bold longitudinal stripes. True to its common name, it holds a characteristic head-down posture as it moves through the water column, a quirk shared across much of the family Anostomidae. In the wild it forms large shoals, grazing on aquatic plants and invertebrates in well-oxygenated currents. In the aquarium, the social dynamics get a bit complicated. Keep too few and individuals become territorial and scrappy with one another, so a group of six or more in a spacious tank is the way to go. Suitable tankmates include larger characins, loricariids, doradids, and calm cichlids. Rheophilic species that appreciate similar water movement are a particularly good fit. Breeding has not been documented in captivity. This is a rewarding fish for an intermediate keeper who can give it the space and company it needs.