Rio Nanay, shallow area near roots of the fallen tree, Peru

117th place in Biotope Aquarium Design Contest 2019

United Kingdom. Radek Cichno

Volume: 160 L
Dimensions: 100x40x40 cm
List of fishes: Corydoras loretoensis WC, apistogramma cacatuoides, Hyphessobrycon eques
List of plants: Sagittaria subulata, Pistia Stratiotes
Description of decorations: River sand mixed with 1ml gravel, river pebbles and stones. Roots and branches of oak, branch or black alder with cones. Few leaves of palm tree for decoration.
Description of equipment: Aquael ASAP internal filter 500l/h, 4x 5 watt led light 300 lumen, 100W heater
Water parameters: Temperature 26°C, GH – 12°dH, KH – 6°dH, pH 6,8.
Additional info: Weekly water change of 25% tap water and 10% RO


Description of the area surrounding the biotope: The Nanay River (315 km) is a river in northern Peru. It is a tributary of the Amazon River, merging into this river at the city of Iquitos. The lower part of the Nanay flows to the north and west of the city, while the Itaya River flows to the south and east. Other nearby settlements on the Nanay River include the villages of Santo Tomás, Padre Cocha, and Santa Clara. During periods when the river is low, the many beaches along the Nanay are popular destinations. The Nanay belongs entirely to the lowlands, and is very crooked, has a slow current and divides into many canos and strings of lagoons which flood the flat, low areas of country on either side. It is simply the drainage ditch of districts which are extensively overflowed in the rainy season.

Description of the underwater landscape of the biotope: a slow-moving channel flowing through forested swamps or wetlands. As vegetation decays, tannins leach into the water, making a transparent, acidic water that is darkly stained, resembling tea.
River is lower in nutrients than whitewater rivers and have ionic concentrations higher than rainwater. The unique conditions lead to flora and fauna that differ from both whitewater and clearwater rivers.

Description of the parameters of the habitat: The Nanay is a blackwater river and it has a high fish species richness, including several that are well-known from the aquarium industry. Some of these, notably green discus, are the result of accidental introductions that happened in the 1970s.

List of fishes and invertebrates occurring in the nature biotope:

List of plants found in the nature biotope:

Threats to the ecology: Deforestation due to land being used for palm tree plantations. Another treat is disposing waste and rubish to the river.

Sources of information:

Comments of the members of the jury of Biotope Aquarium Design Contest 2019