bam Demanding level

Igarapé do Aturiá, Rio Negro, Brasil

Sponsored by

Brazil, Amazonas, Comunidade do Aturiá

As the wet season advances and water levels rise, the once clear Igarapé do Aturiá gets flooded by the incredibly dark and tannin-rich water from the Rio Negro. Its very white and fine sand bottom gets mostly covered by leaf litter and a myriad of botanicals, including Macacarecuia pods (Couroupita guianensis) and the naturally “weaven” crownshafts of Jará palms (Leopoldinia pulchra).

Fallen trees and branches create areas of slower current where debris accumulates and where the bottom remains exposed and the occasional sunlight gets trough, the contrast between the dark, decaying matter and the fine white sand is stark.

This biotope project was created to celebrate and eternize the memories from my visit to this magical place. In the wine-like dark red water of Aturiá a dream came true as I observed Paracheirodon axelrodi in the wild for the first time. Their red bodies almost blending with the surroundings, making the unmissable iridescent, neon blue stripe to stand out divinely.

Submitted by
Andre Muxagata Minguini
-2.5730000, -60.3724670
Geographical region
South America
Drainage Basin
River catchment
Rio Negro
Water body type
Water body name
do Aturiá
Water body part
River mouth
Water body course
Lower course
Water body: tributary of
Tributary name
Rio Negro

Videos above and below water

Water Chemistry

Water information

Water type
Fresh water
Water color
Black water
Water transparency
Concentration of sediments
Water temperature
27 °C
Water flow/curent

Chemical parameters

Dissolved Oxygen
78.4 %

Aquarium information

Aquarium description

Set-up date
June, 2023
Aquarium decoration

This biotope project was created to celebrate and eternize the sun-baked black water in my heart.

What impressed me the most in my visit to the biotope and I really wanted to highlight was how tannin-rich the water is and how the direct and indirect sunlight penetrates the underwater world to drastically affect how colours are perceived.

All the materials used on this project were collected from the biotope surroundings: 10Kg of fine white sand, driftwood, leaves and a large variety of seeds and pods hand-picked from the forest floor; including Macacarecuia pods (Couroupita guianensis) and the naturally “weaven” crownshafts of Jará palms (Leopoldinia pulchra).

The main piece of driftwood was spotted in the bottom of a Igarapé while I snorkelled and in order to roughly reproduce the position that it was found was screwed to a ceramic tile using stainless steel screws. Two mesh bags containing aquasoil and one containing lava rocks were added around the base and capped with sand to add height, stability and provide a nutritional base for the Eleocharis to grow on.

Aquarium equipment

The filtration is done by an Oase Biomaster 350 filter (1100l/h) with an integrated 150w thermostat. Media consists of one basket with sponge and 3 baskets with Seachem Matrix.

The lighting consists of one Chihiros B Series B60 running at 40% intensity (around 900 lumens) and one Chihiros Z Light Tiny (400 lumens) to spotlight and mimic sun rays reaching the bottom of the Igarapé.


  • Paracheirodon axelrodi (Characidae)
  • Dicrossus maculatus (Cichlidae)

Wetland plant:

  • Eleocharis sp. (Cyperaceae)
Fish care

Fish are fed once a day mostly alternating between live (daphnia, baby brine shrimp) and frozen (mosquito larvae, bloodworms, tubifex worms) foods with the ocasional use of flakes or small granules.

Plant care

There’s only a small number of Eleocharis sp. in the tank and although growing very slowly, the plants do very well without the need of any special care.

Water care

Weekly water changes of 30-40%. The replacement water is aged in a water tank containing pieces of driftwood, leaves and botanicals bagged in laundry bags. It’s soft (around 1 dKH), has a pH of 6.0 and temperature of 27°C.

Blackwater water conditioner is also added directly to the tank to replenish tannins. The canister pre-filter is cleaned up every 2 weeks and a full canister cleaning is done every 2 months.


60 cm
35 cm
40 cm
84 L

Substrate in aquarium

Stone form
Submerged terrestrial vegetation