Lawean River Stream, the border between Probolinggo Regency and Pasuruan Regency, East Java Province, Indonesia

_th place in Biotope Aquarium Design Contest 2020

Volume: 54 liters
Dimensions: 60x30x30 cm
List of fishes: Barbodes Binotatus
List of plants: Lindernia Crustacea, Alternanthera Philoxiroides, Imperata Cylindrica, Algae
Description of decorations: All decorations are taken from nature, such as river sand mixed with a little mud (due to floods that occur during the rainy season), river rocks, branches and dry bamboo leaves, with the hope that the survival of the aquatic biota in the aquarium can adapt well and be comfortable like the original environment they.
Description of equipment: Internal filter: Yamano SP-1200, lighting: modul LED DIY 5,6 watt
Water parameters: Temperature is 24-28°C, pH 7,1-7,5
Additional info: Water changes are made once a week as much as 25% of the aquarium water using a small hose so as not to disturb the comfort of the aquarium environment. The lighting is set in such a way as to imitate the length of time the sun illuminates the Lawean River, which is about ± 9 hours. With such lighting arrangements, temperature changes are almost the same as in nature.


Description of the area surrounding the biotope: The flow of the Lawean River originates from the springs of the Bromo-Tengger Mountains which are separated into many rivers to the north of Java Island in the east. The tree species are overgrown with bamboo trees and weeds, with rocks that are carried away by flood currents during the rainy season. Water discharge will decrease drastically during the dry season (between May and October) with temperatures reaching 30-32 ° C at daytime and 23-28 ° C at night.
Description of the underwater landscape of the biotope: The source of the current flows from the Bromo-Tengger Mountains area. Sandy riverbed with little residual silt from flooding and drainage of rice fields irrigation. Many rocks are overgrown with algae in this river flow, as well as many fallen branches and dried bamboo leaves.
Description of the parameters of the habitat: Clear water (dry season) and muddy cloudy water (rainy season), pH 7-7.6 temperature in the dry season 30-32 ° C (day) and 23-28 ° C (night).
List of fishes and invertebrates occurring in the nature biotope: Barbodes Binotatus, Clarias Batrachus, Channa Striata (spesies invasif), Nemacheilus Masyai, Gerridae, Larva Anisoptera.
List of plants found in the nature biotope: Algae, Lindernia Crustacea, Alternanthera Philoxiroides, Imperata Cylindrica, Ipomoea Aquatica, Nasturtium Montanum Wall (plant species that are rarely found in this Lawean River).
Threats to the ecology: The flow of the Lawean River 20 years ago was still used as a means of fishing on weekends with family by the surrounding community. This activity in the last 15 years has been rare and even the most important people have come to visit or unwind the hustle and bustle of the city. The reason is that this river flow has now become part of the sand mining area by related parties. As a result, the river land is getting narrower and the survival of the flora and fauna around the river is threatened. Not only that, the use of fish bombs and fish stun tools is often done by young people who have minimal knowledge of the environment, so the mortality rate for fish from the largest to the smallest is inevitable. It is no wonder that in the next few years the beautiful flow of the Lawean River will only be an old story.
Sources of information: This biotope is the result of my own research because there is no information about the ins and outs of this river:

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