Dimensions 30 × 30 × 30 cm
Title Flooded Bank of an Unnamed Blackwater Stream in the Sungai Kotawaringin Watershed on Bangka Island, Indonesia
Volume 19L
Background black vinyl window film
Lighting 3000k lightbulb - on for 12 hours a day
Filtration Hydor Professional 250 Canister Filter
Plants Nepenthes gracilis
Animals 4x Parosphromenus bintan (1:3 - M:F)
Materials dead hardwood, sand, peat, leaf litter, botanicals, and sticks from various species of hardwood (magnolia, oak, catappa, etc)
Additional Information This biotope is a replication of a flooded section of a stream bank during the wet season. Parosphromenus bintan are found in blackwater streams on Bangka Island, including ones in the watersheds of the Kotawaringin and Menduk (Shi et al. 2021). With heavy rain, small streams swell in size and flood their banks, allowing fish to explore and utilize new habitats and resources. A decayed wooden stump created from multiple pieces of wood provides an ideal location for a group of Parosphromenus bintan to stay. Various nooks and crannies in the stump, along with a dense covering of leaf litter offer many areas for fish to retreat into (which they sure like to do). While catching a glimpse of the fish is difficult, they are content in this space, having bred multiple times. Distilled water is used for this aquarium in order to realize the low levels of dissolved solids in the habitat. The organic material ensures that the water is constantly stained with tannins.
I chose to utilize Nepenthes gracilis as the sole plant as it tolerates submersion and will thrive despite having its roots inundated. It is a widespread species in the lowlands of Southeast Asia, it being a sympatric species with many Parosphromenus is highly likely. In addition, invertebrates would be attracted to the undersides of the pitcher lids to seek the exuded nectar and for cover during the wet season, a fatal mistake as this species of utilizes raindrops to flick insects downwards into the pitcher (Bauer et al. 2012). With the Nepenthes attracting insects, the Parosphromenus eagerly await for any that might find their way onto the water's surface.
References
https://www.fierceflora.com/nepenthes-gracilis/
https://www.natureinstock.com/search/preview/pitcher-plant-nepenthes-gracilis-in-thesabangau-peat-swamp-forest/0_12530196.html
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0038951
https://www.biotaxa.org › zootaxa.5060.1.3
I commend the aquascaper for packing so much into a small tank yet ensuring it remains suitable for the inhabitants. The inclusion of the terrestrial Nepenthes species provides us with a whole other 'world' above the surface and also offers context to the biotope allowing us to picture the entire scene as it might appear in nature.
For me this display just edges into second place over its nearest competitor because the aquascaper has used a small tank making the biotope more appealing to a greater number of aquarists and potential biotopers; our modern way of living often means people do not have the space to showcase a large aquarium yet here the aquascaper has proven that with careful study appropriate choices and faithful replication a slice of an Indonesian stream can be placed into even the smallest home.
Finally I appreciate the choice of fish: small characterful and engaging. This display manages to provide visual stimulation and behavioural interest all the while being faithful to the biotope.