Under palm tree on the shore of the Tapajós river, Brazil

91th place in Biotope Aquarium Design Contest 2019

China. Zhao Wentao

Volume: 96 L
Dimensions: 40x40x60 cm
List of fishes: Nannostomus rubrocaudatus, Hemigrammus bellottii, Dicrossus maculatus
List of plants: Eleocharis parvula, Eleocharis montevidensis
Description of decorations: In order to completely restore the original water quality environment of tapajos, I laid some water grass mud on the back of the bed. The sand and water grass mud in the first half are separated by wooden sticks A large number of palm leaves and a small amount of Terminalia leaves form the main environment, providing a large amount of shelter for fish and microorganisms, and decaying very slowly. The yellow tone gives a feeling of being hot in the tropics. The sand uses delicate and soft cosmetic sand to imitate the white sand that is seen in the original environment and is not easily blown by the current.
Description of equipment: FLUVAL 206 external filter
Atman cf800 external filter
led 50w
EHEIM Rain tube
Water parameters: 29°C, pH 6.5, tds 105
Additional info: I had 5 Dicrossus maculatus at beginning,when came to bred,I took out two.


Description of the area surrounding the biotope: For most of its length the Tapajós runs through Pará State, but the upper (southern) part forms the border between Pará and Amazonas State. The source is at the Juruena–Teles Pires river junction. The Tapajós River basin accounts for 6% of the water in the Amazon Basin, making it the fifth largest in the system. The Tapajós is one of three major clearwater rivers in the Amazon Basin

Description of the underwater landscape of the biotope: The first major cataracts on the Tapajós River are near Itaituba, approximately 200 km from its mouth. Migratory fish, however, are able to pass these rapids. Numerous rapids stud the middle and upper Juruena and Teles Pires Rivers. The lower Juruena has floodable forests and there are small low-lying areas subject to seasonal inundation scattered throughout the Tapajós Basin. It has a large number of pure white sand sandy riverbeds, dense grasses, and empty area covered with organic matter. There are cascading fallen leaves under the trees near the river bank, and various fish shuttle through them.
I hope to present a situation under a palm tree in the rainy season. The protagonist is the Dicrossus maculatus.The rising water gives them a chance to enter the river beach to complete the mission of a lifetime.

Description of the parameters of the habitat: At its mouth the Tapajós River isconstrained by the water of the Amazon River.Consequently, its physicochemical parameters arestrongly affected by the whitewater of the AmazonRiver, and it exhibits high pH, conductivity, and TDS values until 50 kilometer upstream. ,except for the high conductivity and TDS values.Physicochemically, the water of the Tapajós River exhibited characteristics lying between those of the Amazon and Negro rivers waters.pH 6.5 ± 0.4; conductivity= 14.4 ± 13.1

List of fishes and invertebrates occurring in the nature biotope: Cyphocharax gangamon Vari, 1992
Characidium cf. zebra Eigenmann, 1909
Astyanax bimaculatus (Linnaeus, 1758)
Hemigrammus analis Durbin, 1909
Jupiaba acanthogaster (Eigenmann, 1911)
Knodus cf. shinahota Ferreira & Carvajal, 2007
Moenkhausia collettii (Steindachner, 1882)
Catoprion mento (Cuvier, 1819)
Erythrinus erythrinus (Bloch & Schneider, 1801)
Denticetopsis seducta Vari, Ferraris & de Pinna, 2005
Callichthys callichthys (Linnaeus, 1758)

List of plants found in the nature biotope: Echinochloa polystachya (Poaceae)
Polygonum ferrugineum (Polygonaceae)
Oryza perennis (Poaceae)
Eichhornia crassipes (Pontederiaceae)

Threats to the ecology: Munduruku has been in the middle and upper reaches of RioTapajós since ancient times. The thickly vegetated shores, misty hills and untamed waters, in the next few years, the Brazilian government – with financial and engineering support in China and Europe – hopes to build the river by building 49 major dams on Tapajós and its tributaries Become the largest grain canal in the world. For the Brazilian government, this large-scale plan for the open Tapajos Basin (roughly the French region) is the key to national economic development and trade with China. For local politicians, this is an opportunity to industrialize, expand and enrich the business of nearby cities, whose population is expected to double in the next 10 years. For an eco-lover, this is unfortunately frustrating. These plans will greatly affect the local ecological environment. These plans to build dams were delayed due to local indigenous resistance but were difficult to cancel completely. In our country, the government often emphasizes that we should not take the old road of pollution control, but it is clear that our assessment of the impact of international investment on the ecological environment needs to be improved.
“This is a historic moment for the Amazon. We have seen previous economic booms – rubber, logging and mining – that caused social conflict and environmental damage, but the proposed development along the Tapajós covers a much wider area and would have a much more profound impact,” said Alcilene Cardoso of the Amazon Environmental Research Institute.

Sources of information:
Stream ichthyofauna of the Tapajós National Forest, Pará, Brazil
Article  in ZooKeys 580(1):125-144 · April 2016
Aquatic herbaceous plants of the Amazon floodplains:
state of the art and research needed Maria Teresa Fernandez Piedade
aqua TV
Brazil’s mega hydro plan foreshadows China’s growing impact on the Amazon by Jonathan Watts from The Guardian

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