Rio Poranga, tropical stream in the region of São Gabriel da Cachoeira, Amazonas

_th place in Biotope Aquarium Design Contest 2020

Volume: 500 l
Dimensions: 140x60x60 cm
List of fishes: Corydoras duplicareus 
List of
plants:  Eleocharis acicularis, Echinodorus amazonicus

Description of decorations: The found root branches and wood were used to build arrangements in the aquarium, which were specially arranged differently to create a gradual slope of the terrain. The substrate was sprinkled with river sand purchased in an aquarium store. Larger and smaller (personally found) dark roots imitating the sunken roots of tropical trees and shrubs growing along the riverbank served as an additional decoration. The effect of a naturally silted bottom was created by applying a small amount of crushed roots and dried leaves, which were gently sprinkled on the surface after cooking, and then everything settled to the bottom, and over time the desired natural effect was obtained. All elements of the aquarium decor have been properly cleaned and heat treated to keep the fish safe. The whole thing is to imitate the shoreline of a tropical river with tree roots and plants. A matte self-adhesive foil was used to make the background, and then a beige cardboard approximately 1 cm away in the color of a paper eco bag, which was additionally highlighted with RGB tape. In the space between the back glass and the cardboard attached to the wall, the roots are placed at the top, and the dry grass at the bottom. This is to mimic the depth of the aquatic landscape. This technique has been called “Deep shadow”.

Description of equipment: Filtration: JBL CristalProfi e1901 greenline – 1900l / h., 15l bucket divided into 5 baskets with media, one is a protective sponge, the other four are ceramics, which creates a complete biological division in the filter. The primary lighting is Aquatlantis Easy LED Freshwater, 1047mm, 6800 ° K-52w Eady Led Control, which simulates the natural and gradual effects of sunrise and sunset. I also use an additional 4000K-10W LED lamp with warm light that mimics the sun’s rays. The blue background behind the aquarium is lit by a strip of white RGB LEDs.

Hardware descriptions: Filtration: JBL CristalProfi e1901 greenline – 1900l / h. 15l bucket divided into 5 baskets with media, one is a protective sponge, the other four are ceramics, which creates a full biological division in the filter. The primary lighting is Aquatlantis Easy LED Freshwater, 1047mm, 6800 ° K-52w Eady Led Control, which simulates the natural and gradual effects of sunrise and sunset. I also use an additional 4000K-10W LED lamp with warm light that mimics the sun’s rays. The beige background behind the aquarium is illuminated by a strip of several white RGB LEDs.

Water parameters: Temperature: 25°C, pH: 6.5, Hardness: Gh 6, Conductiviti 40 ppm

Additional info: The water in the aquarium is replaced at 20% every 10 days. Bacteria are also added with each water change.


Description of the area surrounding the biotope:

GPS (1°07’34.0″N 66°51’01.8″W)

The Rio Poranga, also known as the Igarape Poranga, is a tributary of the upper Rio Negro in the Amazonas state in the Sao Gabriel da Cochaeira region of Brazil, near the village of Cucui in the north and near Balaio, towards Sao Gabriel da Cochaera. Exactly the biotope is close to the airport, which can be seen on the maps after entering GPS. The outline of the river is very clearly visible, although it is not described. Despite its existence, this river is not marked on the maps. The same applies to the other known rivers in the area that exist and are home to various fish species. The inhabitants do not need such information and efficiently use the names of these rivers, which are available in the literature, although they are not on the maps. They can provide such information to those who will not see it on the maps and to those who have not personally visited these places. Based on this information, the site of Rio Poranga was also precisely located. Of course, there are many other tropical rivers in the area, Rio Demiti to the south and Igarape Eni to the north. Between these rivers is the Rio Poranga, thankfully marked on the maps. São Gabriel da Cachoeira is the third largest municipality in Brazil by territorial area and the second largest in the Amazon. It is also the northernmost city of the Amazon and part of its territory is located in the Pico da Neblina National Park, which covers an area of over 22,300 km2. Pico da Neblina National Park is characterized by a great variety of habitats due to the anorographic division of vegetation (from 100 to 3014 m above sea level) and a mosaic of soils with a predominance of lowland primeval tropical forests forming the ecosystem However, the summit itself is located in Santa Isabel do Rio Negro and São Gabriel da Cachoeira is located in the lowlands. It is not far from the equator and the climate is suitably hot and humid. The municipality covers 36,900 hectares (91,000 acres) of the Morro dos Seis Lagos Biological Reserve, established in 1990. The reserve covers 257,000 hectares (640,000 acres) of the Autochthonous Territory of Balaio, approved in 2009. The municipality also covers 809,000 hectares (2,000,000 acres) of the indigenous territory of Cué-cué / Marabitanas, declared in 2013 7,999,000 hectares (19 770,000 acres) of the Alto Rio Negro Autochthonous Territory, founded in 1998. All this beautiful area belongs to.

Description of the underwater landscape of the biotope: The biotope shows the typical habitat of Corydoras duplicareus. Their underwater world in this river is the color of lightly brewed tea. It is not typical black water like in Rio Nego, but the water has a warm shade. There is not much vegetation in this area due to the shade. There are many fallen leaves, such as palm leaves, and the remains of organic plants, including fruits and roots. There are many submerged roots of trees and shrubs growing in the Theopic forest, which gives this place a very specific and exotic character. At the bottom you can see river sand and sunken pieces of wood of various sizes. Dark but quite transparent water, slightly shaded water reveal the full range of colors of fish living in these areas.
Description of the parameters of the habitat:

According to water analysis Water analysis obtained the following pH values 4.5-4.6, zero hardness. Water temperatures of around 28 degrees C (30 degrees C in the shallows) were recorded.

Conductivity 10-20.

The color and chemical composition of the water is the result of a large number of leaves and fruit which, falling from the trees, rot and emit tannins and humic acids – strongly acidifying and tinting the water brown.

List of fishes and invertebrates occurring in the nature biotope: Corydoras duplicareus, Corydoras Adolfoi, Paracheirodon axelrodi, Brachyrhamdia rambarrani

List of plants found in the nature biotope: Due to the prevailing conditions in the river where most places are shaded by tropical forests, there are really few plants. There are places with more plants. Most often it is in the coastal zone. These are among others: Eleocharis acicularis, Echinodorus amazonicus, Echinodorus sp., Myriophyllum braziliensis, Ceratopteris spp., Cabomba caroliniana, Eichhornia crassipes.

Threats to the ecology: Water resources in the Amazonia affect all natural and human-altered ecosystems in the region, including their human populations. Evapotranspiration by the Amazon forest provides water vapor that is transported by wind to other regions of Brazil and to neighboring countries. The enormous quantities of water involved in hydrological processes in Amazonia give great importance to the region’s water resources and to potential impacts if these cycles are altered. The diversity of fish and other aquatic organisms is enormous, as is the importance of this fauna as economic and food resources for the human population. There are impacts from pollution, including mercury methylation in hydroelectric reservoirs. Dams also block migration of fish and alter the flooding cycles of rivers. Hydroelectric dams release methane, thereby contributing to global warming. The chemical characteristics of different types of water affect processes such as the transport of organic carbon, the supply of nutrients to the plankton that are the base of the food chain in aquatic ecosystems, and the quantity of bio-available ions that affect sensitivity of organisms to copper and other toxic elements. Several of the major rivers in the region drain more than one country.

The Amazonian forest is gradually declining in virtually every area, many square kilometers of forest have been cleared over the last century, most of them in recent decades. This was due to many factors. First of all, burning forest areas and their legal and illegal cutting. The land obtained in this way is intended for new pastures for cattle, soybean, maize, sugar cane and oil palm (for biofuels). Destruction is also caused by expanding cities and large investments, such as the construction of power plants or mines that exploit local natural resources, including oil. Global warming is also destroying the fauna and flora of the Amazon. Scientists believe that a rise in global temperature of more than 2 ° C above pre-industrial levels will result in catastrophic flooding and drought, rising sea levels, and heat waves and epidemics. The importance of the Amazon for the Earth’s climate cannot be underestimated. Keeping temperatures on our planet at the right levels is not only important, it is also a sufficient source of freshwater to influence ocean currents, and its lush vegetation absorbs the most carbon dioxide in the world. In turn, the destruction of such a large area of wet equatorial forests will make it impossible to maintain the global temperature at a level that would prevent natural disasters. The result of these phenomena is the destruction of biodiversity and the extinction of many species of plants and animals. Indirectly, it affects the quality of life of all of us, because it stabilizes the Earth’s climate and affects the weather by regulating rainfall and evaporation of water from the soil.

Millions of animals, especially from the Amazon, are illegally sold in Brazil and abroad, illustrates the Wildlife Trafficking in Brazil report, supported by USAID, through the Wildlife Trafficking Response, Assessment, and Priority Setting (Wildlife TRAPS) project.

River turtles, fish, jaguars, and birds are the most frequently poached in the Amazon region. According to the seizure data between 2012 and 2019, the largest illegal wildlife trade in the Brazilian Amazon, by volume, is the smuggling of river turtle eggs. They are used as decorative items (shells), and for culinary purposes.

Over 30 ornamental fish species were trafficked to meet regional and international demand. In these seven years, Tetra-cardeal, Silver Arowana, and critically-endangered Zebra Pleco were among the most seized. For consumption, the pirarucu, one of the world’s largest freshwater fish species, is the principal target for poaching and trafficking.

The report points out that lack of quality data and difficulty coordinating monitoring of illegal commerce conceal the extent of illicit trade. To reduce illegal wildlife trade, the study offers several recommendations, including developing a national strategy to combat trafficking, enhanced data collection and shared information across agencies, to strengthen environmental crime legislation.

Sources of information:,%20Ecotropica%2013-1.pdf

Amazonia: Water Resources and Sustainability, October 2017

DOI: 10.1007/978-3-319-41372-3_6

In book: Waters of Brazil (pp.73-88)

Projects: Ecology and monitoring of vegetation in oligotrophic wetlands in the Central Amazon (PELD MAUA)Conservation Genetics of Fish. PDF

Comments of the members of the jury of Biotope Aquarium Design Contest 2020