Lake Tanganyika, northwest coast, near the town of Uvira, Democratic Republic of the Congo

50th place in Biotope Aquarium Design Contest 2017

russian_federation Russia. Sergey Lobanov

Volume: 380 L
Dimensions: 180x45x47 cm
List of fishes: Tropheus duboisi, Tropheus moori var. “Bemba”
List of plants: algae
Description of decorations: The natural stones are round, in shape and color they are like stones in the nature biotope of the Tanganyika lake. On the bottom there is quartz sand, similar to the soil of the biotope of the Tanganyika lake.
Description of equipment: Eheim classic 2217 external biofilter, mechanical submersible filter PowerHead 2000 l/h, light: T5 39W x 2 Sylvania GroLux.
Water parameters: Temperature is 25°C, рН – 8, GH – 10

Description of the area surrounding the biotope: The Tanganyika lake is the oldest. Tanganyika is located at an altitude of 773 meters above sea level. It is the second deepest in the world after the Baikal lake and the deepest lake of the African continent. The greatest depth of the lake is in the southern part and is 1470 meters. The average depth of this largest freshwater reservoir in Africa is about 572 meters. It is distinguished exclusively by transparent water up to 33 meters. Precipitation falling during the rainy season (from October to December and from February to April in the north of the lake) increases the water level in the lake and carries a large amount of silt to it. The water level in the lake has so far been considered unchanged, but there is a tendency to its gradual decline. Tanganyika is characterized by long-term fluctuations in the water level of 4 m.

Description of the underwater landscape of the biotope: The Tanganyika lake is located in the East African rift fault. The fault is more than 7000 meters deep, of which 6000 m are sedimentary deposits accumulated on the lake bottom for thousands years. The north-west coast is a cliff area. The zone of talus consists of rocks and fragments of rocks of different sizes. Among their conglomeration crevices and caves were formed, which are excellent shelters for many fish. There are absolutely no higher water plants, but in the clear water under the rays of the sun on the rocks algae rapidly developing. In the zone of rocks the banks abruptly go to a depth of 5 to 15 m, the bottom is covered with huge fragments of rocks forming large caves. There are no shoals and there are also no higher aquatic plants, but a powerful carpet of algae can be found even at great depth.

Description of the parameters of the habitat: The lake water is very transparent (up to 33 m). The pH varies between 8.0-9.5. The conductivity of the water is approximately 609-620 μS. The water is fresh, but with an increased content of magnesium salts. The total hardness in different parts of the lake ranges from 12 to 19 degrees. The temperature keeps in the range from 24 to 30°C, with a decrease at great depths.

List of fishes: Cichlids from genus Eretmodus, Julidochromis, Spathodus, Tanganicodus, Telmatochromis, Tropheus and Lamprologus.

List of plants: N/A.

Threats to the ecology: The ecological situation around the lake from year to year is becoming more strained, especially in its northern part, near the coast of Burundi. The water of the Tanganyika lake constantly get industrial, agricultural and domestic waste. Due to the lack of running water and sanitation, residents of coastal villages often do their natural needs directly into the lake, while they take water for domestic needs from the same water body. As a consequence, outbreaks of infectious diseases are regularly observed in Burundi, primarily cholera. Another problem threatening the ecosystem of Tanganyika, is new plant species. Of these, the greatest danger, according to scientists, has water hyacinth (Eichhornia crassipes). Growing at high speed, this plant covers the surface of the lake with a dense carpet, which prevents access to sunlight, and also disrupts the natural oxygen regime of the reservoir. This leads to the migration or death of organisms living in the lake. In addition, these plants create obstacles for navigation.

Sources of information: a book by Sergey Kochetov “Cichlids in aquarium”, 2000;Танганьика; http:/Танганьика_озеро;