Lava River in the middle reaches, canyon near the village of Vasilkovo, Russia

14th place in Biotope Aquarium Design Contest 2017

 Russia. Igor Repin

Volume: 500 L
Dimensions: 150x60x65 cm
List of fishes: Squalius cephalus, Rutilus rutilus, Phoxinus phoxinus
List of plants: N/A
Description of decorations: Fine light sand, pebbles, calcareous stones with fossils of the Ordovician period, dry branches of trees with leaves, structural background for the aquarium.
Description of equipment: Eheim 2217 external filter, flow pump 1000 l/h, Aqualighter LED lights, compressor Tetratec APS 400
Water parameters: рН 7.5, КН 6, GH 8

Description of the area surrounding the biotope: The Lava River is 31 km long and starts in peat bogs to the south of Naziya settlement. In the upper and lower reaches, the Lava flows in a shallow valley. On the middle reach, however, the river cuts deep into the limestone, up to 30 m, and makes a picturesque canyon about 7 km long. On the banks leaf trees grow: elm, ash, alder. In the spring waters destroy the calcareous layers, and the stone blocks fall into Lava. Limestone, which forms the walls of the canyon, is rich in fossil organisms of the Ordovician period. These are the remains of numerous echinoderms, trilobites, bryozoans, brachiopods and cephalopods. Their age is 485-443 million years. Often fossils can be found right in the river bed, among the pebbles. In the lower course, the river bottom gradually becomes muddy. A few kilometers north the Lava flows into the Ladoga Lake. Lava is a reservoir with pronounced seasonality. In spring, during the melting of snow, the river becomes turbulent and full-flowing, the current is very fast and strong. In April and May, the Lava is popular among athletes, kayakers. In summer the water level gradually falls, and by August the Lava is more like a wide and fast stream. Canyon of the Lava River is a geological monument of the Leningrad Region.

Description of the underwater landscape of the biotope: The bottom of the river is covered with plates, stones, calcareous pebbles and sand. In shallow water, the stones are covered with algae. The water has brownish color, rather transparent. The flow in this part of the river is relatively fast, there are even small thresholds. That is why at the bottom you can find only large driftwood or fallen trees, small branches and leaves are carried away by the current. Here there are chub, belica, gudgeon, etc. The chub, represented in the photo, were caught as fry in the Lava river, and for 3 years they are kept in an aquarium. Actually, this area of the Lava has a few aquatic plants due to the rapid flow. The rocks are rich in water moss Fontinalis antipyretica. Among the pebbles on the shore, Cardamine amara often grows. In this part of the Lava rhyophilic organisms live that need high concentration of oxygen: mayflies, stoneflies, caddisflies, etc.

Description of the parameters of the habitat: The water is clear, brown, alkaline (pH 8), fairly stiff (KH 8, GH 10), saturated with oxygen.

List of fishes: Aspius aspius, Squalius cephalus, Rutilus rutilus, Phoxinus phoxinus, Esox lucius, invertebrates of Heptageniidae, Hydropsychidae.

List of plants: Fontinalis antipyretica, Cardamine amara (ner the coast)

Threats to the ecology: In recent years, the Lava River suffers from pollution, which is clearly harmful to the inhabitants of the river and endangers the existence of this unique biological community.

Sources of information: http://lavrovo.clan.su/index/0-5; https://www.youtube.com/watch?v=rodCxQRBVzE; http://ru-travel.livejournal.com/28344004.html; https://wiki2.org/ru/Лава_(река,_впадает_в_Ладожское_озеро); https://kamaran.ru/leningradskaya-oblast/sankt-peterburg/kanon-reki-lavy-1321; https://vk.com/videos-52983980?z=video-52983980_456239234%2Fpl_-52983980_-2