Brazil, Amazonas, Barcelos
This biotope replicates a dry-season leaf-pack zone of Igarapé do Daracuá, a blackwater forest creek near Barcelos, Rio Negro, Brazil. My motivation was to document the true ecological niche of Paracheirodon axelrodi, moving beyond decorative “Amazon” tanks to recreate the conditions where Cardinal Tetras form dense schools: pH 4.1, conductivity 10 µS/cm, and the absence of a mineral substrate.
The composition centers on a single shaft of light penetrating the igapó canopy, a phenomenon documented in Mikolji’s 2022 footage of Daracuá. This beam illuminates a substrate composed entirely of Mauritia flexuosa palm fronds with branch tangles, replicating the low-PAR environment where true aquatic plants cannot survive, as described by Walker (1995).
The most interesting feature is that 25 Cardinal Tetras exhibit natural monospecific schooling behavior within the leaf pack, foraging on biofilm as described by Knöppel (1970). The absence of sand, aquatic plants, or non-biotope elements focuses attention on habitat function rather than aesthetics.
- GPS
- -0.1415000, -63.1858826
- Geographical region
- South America
- Drainage Basin
- Rio Amazonas
- River catchment
- Rio Negro
- Water body type
- Igarapè
- Water body name
- do Daracua
- Water body part
- River mouth
- Water body course
- Lower course
- Water body: tributary of
- River
- Tributary name
- Rio Negro
Videos above and below water
