Ternetzi Headstander (Anostomus ternetzi)
 
The Ternetzi Headstander, scientifically known as Anostomus ternetzi, thrives across a wide expanse encompassing the Amazon, Araguaia, and Orinoco River basins. It's also found in the coastal rivers of the Guianas, typically inhabiting rocky areas with swift currents. These fish congregate in sizable shoals, feeding on a diet that includes crustaceans, insects, plant matter, and worms.
Reaching a moderate size, Ternetzi Headstanders require a spacious aquarium, ideally measuring at least 4ft x 18″ x 18″, or larger. Juveniles grow rapidly and should be given ample space from the start to prevent stunting. A mature aquarium with a sand or small-grained gravel substrate, sturdy driftwood pieces, and open swimming spaces is essential. While plants aren't necessary, robust species like Anubias spp. and Java Fern are recommended, as these fish tend to consume plants.
Powerful filtration, preferably external canisters, and high oxygenation are crucial for maintaining water quality. Regular partial water changes are necessary to minimize nitrogenous waste. Tight-fitting covers are essential due to their jumping tendency.
In terms of social behavior, Ternetzi Headstanders can be quarrelsome, so it's best to keep them either individually or in groups of at least 8 individuals introduced simultaneously to spread any aggression. Suitable tankmates include medium-large peaceful cichlids, medium-sized characins, talking catfish, and suckermouth catfish. However, tiny fish may be preyed upon, and long-finned species might be nipped at.
 
Species: Anostomus ternetzi
Common Name: Ternetzi Headstander, Giant Pencilfish
Origin: Brazil, Colombia, and Peru in South America
Diet: Omnivore
pH Range: Alkaline, 6.5 – 7
Temperature: Tropical, 26-28°C
Breed Type: Egg scatterer
Maximum Size: Approximately 12cm
Sex: Un-sexed