bam Easy level

Small tributary of Rio Paraná, Argentina

Sponsored by

Argentina, Entre Ríos

For this biotope aquarium, as I decided to recreate a shallow water zone, near the margins of the small tributary La Azotea – La Jaula, where the water flow isn’t strong. I chose some of the smaller fish and invertebrates, that prefer to live protected by the floating vegetation, the network of roots, stems and leaves, and the dried leaf litter, driftwood and small rocks that stay accumulated there.

Submitted by
Pedro Mendanha Dias
Approved by
Heiko Blessin & Nathan K. Lujan
-32.1216125, -60.6345291
Geographical region
South America
Drainage Basin
Paraná basin
River catchment
Water body type
Water body name
La Azotea - La Jaula
Water body part
Flood plain
Water body course
Water body: tributary of
Tributary name

Videos above and below water

Water Chemistry

Water information

Water type
Fresh water
Water color
Clear water
Water transparency
Concentration of sediments
Water temperature
Even if, for most of the year, the temperature was between 19ºC and 22ºC, it dropped until 15 ºC, in some winter days, and reached in the summer 28 °C
Water flow/curent

Chemical parameters

6 mg/l
3 mg/l
Dissolved Oxygen

Aquarium information

Aquarium description

Set-up date
October, 2019
Aquarium decoration

Fine river sand, wood, small roundish rocks, dry leaves and botanicals (like, for example, Jacaranda mimosifolia seed pods, a sub-tropical tree native from Argentina).

Aquarium equipment


  • Seachem – Tidal 75, with an adjustable flow, that can arrive till a maximum of 1500 L/h, that I only used in the period that I tried to simulate the rainy season. Because in the dry season the flow is always less strong. This canister filter works with biological filter material.


  • Chihiros E-series RGB90, with a variable photoperiod (dry season: 7h; rainy season: 10h). I used driftwood and floating plants to form shady areas in the aquarium. And I dimmered the LED light, simulating a the natural daylight intensity.
Fish care

I just worry about giving a big variety of quality food (live, frozen, and dry foods). Besides that, the fish never had any problems. Apparently, they live happy, lay eggs, and many Phalloceros caudimaculatus have been born.


  • Palaemon argentinus 4


  • Aphyocharax anisitsi 15
  • Apistogramma borellii 6
  • Corydoras hastatus 11
  • Corydoras paleatus 10
  • Hyphessobrycon eques 14
  • Otocinclus arnoldi 9
  • Phalloceros caudimaculatus 6
  • Rineloricaria parva 4
Plant care

To give some extra nutrients to the plants, and permit that they grow lusher, every 2 months, I put some fertilizer, Aquario’s NEO plants tab (Long lasting and Fe), in the ground. A good option for plants, that doesn’t change the water parameters, and consequently the fauna isn’t affected.

Aquatic plants:

  • Echinodorus grandiflorus
  • Eichhornia sp.
  • Juncus sp.
  • Eleocharis sp.
  • Gymnocoronis spilanthoides
  • Myriophyllum aquaticum
  • Hydrocharis laevigata
  • Pistia stratiotes
Water care

In the dry season I only made a small (approximately 20%) monthly, water change and leave the aquarium water level lower. On the other hand, in the rainy season, I made weekly water changes of approximatly 40%, and add more dry leaves and botanicals, to try to simulate the periodic flood pulses.
I didn’t use a heater, because the temperature differences, between the dry and rainy seasons, in this region of Argentina, are very similar with the portuguese ones.

The bibliography shows that predominant soil texture is characterized, in general, by the predominance of the silt fraction. But has I found extremely difficult to maintain an aquarium with so small diameter particles, I opted to use river sand with a small size grain.


100 cm
42 cm
44 cm
180 L

Substrate in aquarium

Stone form
Submerged terrestrial vegetation


  • → Guía de los Peces del Parque Nacional Pre-Delta by ALMIRÓN, Adriana; CASCIOTTA Jorge; CIOTEK, Liliana; GIORGIS, Pablo
    ISBN 978-987-1363-23-0
  • Biodiversidad del Parque Nacional Pre-Delta by ACEÑOLAZA, Pablo al
  • Características fisicoquímicas y bacteriológicas de los ambientes acuáticos del PNPD posteriores a un período de aguas altas by MIRANDE, Virginia et al
  • Evaluación abiótica y biótica de ambientes acuáticos de un parque nacional entrerriano by MIRANDE, Virginia et al.
  • Las comunidades vegetales del Delta del Río Panrana. Su relación com factores ambientales y patrones del paisaje by MALVÁREZ, Ana Inés
  • → Bleher’s Biotopes by BLEHER, Heiko
  • Peces Pampeanos guía y ecología by ROSSO, Juan José
  • Peces y Ambientes en la Argentina continental by MENNI, R. C.
  • Catalogo de la flora vascular del PN Pre Delta by RODRIGUEZ, Estela Elizabeth; ACEÑOLAZA, Pablo; MUÑOZ, Juan de Dios

Comment by the expert

Heiko Blessin: The set up of the aquarium looks okay, but could be better. Try to combine some rules of aquascaping (the art of design) with the natural look. If you just copy the nature you will never achive an “eye catcher”.

Nathan K. Lujan: I really like the diversity of fishes in the tank. Although it is hard to judge how accurately the natural habitat given the limited description available, the Pantanal underwater is frequently illustrated elsewhere and the tank has an appropriate appearence of clean clear water, good plant growth, and some leaves or detritus on the bottom.