Niger Oto (Hisonotus leucofrenatus)
| Niger Oto Hisonotus leucofrenatus | |
|---|---|
 | |
| Name | Niger Oto |
| Name Lat. | Hisonotus leucofrenatus |
| Synonym | Otocinclus leucofrenatus |
| Family | Suckermouth Armoured Catfishes |
| Family lat. | Loricariidae |
| Order | Catfishes |
| Order lat. | Siluriformes |
| Origin | Brazil |
| Habitat | Forest streams |
| Diet | Limnivore |
| pH | 6.0-7.5 |
| Behavior | Peaceful |
| Keeping | Group |
| Care Level | Moderate |
| Reproduction | Substrate spawner |
| Breeding | Difficult |
| Life Span | 2-4 years |
| Protection | No |
| Metric Units | |
| Size | 5-6 cm |
| Temperature | 20-25 °C |
| Hardness | 1-10 °dH |
| Aquarium | ~ 80 l |
| US Units | |
| Size | 2"-2.4" |
| Temperature | 68-77 °F |
| Hardness | 18-178 ppm |
| Aquarium | ~ 20 gal |
Distribution and habitat
The Niger Otocinclus is distributed in the catchment area of the Rio Ribeira de Iguape and other rivers in southeastern Brazil. They live in waters with dense riparian vegetation, among dead wood and aquatic plants.
Maintenance
The aquarium should have dense marginal planting with roots that provide hiding places and at the same time are part of their diet. A sandy substrate covered with some foliage (sea almond tree, beech), subdued light (floating plants) and a weak current is ideal
No ammonia, ammonium and nitrite should be detectable, the nitrate value should not exceed 100 mg/l. To ensure the water quality and oxygen content, a filter and heater adapted to the aquarium size is required, as well as lighting for the species-appropriate day-night rhythm of the animals.
Diet
They eat the vegetable cover (growth) of stones, wood, plants, etc. and the microorganisms contained therein. For a balanced diet, feed once a day with a high-quality dry food for catfish (granules, pellets, chips, tablets) supplemented with algae leaves, fresh vegetables such as zucchini, broccoli, bruised peas or scalded spinach, plus occasional small amounts of zooplankton, cyclops, daphnia, artemia, mosquito larvae, etc. (live or frozen). Feed only as much as will be eaten within a few minutes, excluding plant foods. Regular and varied feeding promotes health and increases resistance.
Behaviour and compatibility
They are diurnal, live in small schools and are very suitable for a community tank with other peaceful fish. At least 5, but preferably more Niger Otocinclus should be kept together.
Basically, only compatible fish species with similar demands on water conditions and water temperature should be socialized.
Sex dimorphism
The sexes are difficult to distinguish. The females are slightly larger and rounder.
Reproduction and breeding
The spawn is attached to plants, panes or other substrate. The larvae hatch after 2-3 days. The parents do not engage in brood care.
Fry must be fed several times a day with special rearing food (infusoria). In community tanks breeding is hardly possible, because the spawn is easy prey.
Important
They are excellent algae cleaners, but aquarium plants are not damaged.
They also have intestinal respiration to survive in oxygen-poor waters and sometimes come to the water surface for air even in the oxygen-rich aquarium.
The foliage (sea almond tree, beech, etc.) enriches the water with humic substances, naturally lowers the pH and, when rotting, promotes the development of microorganisms, which are a valuable secondary food source.
When fishing, use the finest mesh nets possible so that the hard rays of the pectoral fins do not become entangled.
The well-being of the fish should be monitored regularly. Temperature should be checked daily, pH, hardness and nitrate levels at least every 14 days. Regular partial water changes are recommended, even if the contaminant level has not yet reached the upper limit. Sudden changes in water quality should be avoided. Newly introduced fish must be accustomed slowly to the water in the aquarium.
Further literature can be found in your pet store.
References
Text: Werner Winter; Image: Franz Lowak
Source: BMELV (1998): Tierschutzgutachten - Haltung von Zierfischen (Süßwasser); RIEHL & BAENSCH (2004): Aquarien Atlas Bd. 3, Mergus Verlag; ENGELMANN (2005): Zootierhaltung - Tiere in menschlicher Obhut: Fische, Verlag Harri Deutsch
- Gemäß § 21 Abs. 5 Tierschutzgesetz idgF