bam Demanding level

Rio Tamasopo, San Luis Potosi, Mexico

Sponsored by

Mexico, San Luis Potosi, Tamasopo

I love Central American biotopes, and Mexican setups in particular. And I really like livebeares as well. So in this aquarium I wanted to create a natural looking setup, dedicated to livebearers. I wanted this setup to have the beatiful Xiphophorus montezumae as the main character, and not just as a supporting role.

Along with this I also wanted to create a biotope based on the great work by Rune Evjebjerg and Kai Qvist, and to pay a tribute to their amazing book “A Selection of Freshwater Fish Biotopes in Mexico”.

According to composition, my main focus is on the hardscape and attempt to recreate the look of a natural riverbank. This both affects the use of driftwood, branches, stones, dirt and even DIY hobby concrete.


Submitted by
David Nørholm
Approved by
Juan M. Artigas Azas, Jairo Arroyave & Michael Köck
21.9396496, -99.3965378
Geographical region
Central America
Drainage Basin
Pánuco River Basin
River catchment
Tamasopo River Basin
Water body type
Water body name
Rio Tamasopo
Water body part
Water body course
Middle course
Water body: tributary of
Tributary name
Río Tampaón

Videos above and below water

Water Chemistry

Water information

Water type
Fresh water
Water color
Clear water
Water transparency
Concentration of sediments
Water temperature
25 °C
Water flow/curent

Chemical parameters

7 mg/l
Dissolved Oxygen

Aquarium information

Aquarium description

Set-up date
March, 2023
Aquarium decoration

The composition and choice of hardscaping materials is based in my setup on the idea of recreating a natural looking riverbank.

On the left side, I have made a natural looking riverbank out of hobby concrete, where I have added dirt, stones, pebbles, sticks and branches. This riverbank piece is sloping down towards the right site of the tank. This is done to mimic the look of a natural looking riverbank, sloping down towards the deeper end of the river.

On the top of my riverbank imitation there is a fern, which is intended as an imitation of the vegetation that grows in the transition zone between land and water. The fern’s roots adds to the look of a natural looking riverbank with overhanging terrestrial vegetation. Furthermore, it serves as a hiding place for the fish fry.

Driftwood in various sizes are chosen to recreate the look of fallen logs and tree trunks. Rounded rocks are added to the right site of the tank, because rocks are more present away from the steep riverbank. A couple of stones are hidden in the riverbank though.

Branches, twigs, and leaf litter are added to create the feel of a Central American river bottom, with plenty of sediment. The substrate consists of multiple sizes of sand, pebbles, and gravel to help create the look of the river bottom.

I have chosen to add some Valisneria spiralis and Ceratophyllum demersum to the setup as well. Which is not biotope correct plants, but I have deliberately chosen that anyway. The Ceratophyllum demersum is an invasive species in the biotope, and is therefore partly correct. The Valisneria is not, but I have chosen this specific plant to help create the look of grass-like areas located in the transition zone between land and water.

These grassy types of vegetation get flooded and exposed during the seasonal changes of the river. Most natural present plants from the biotope are not available in the aquarium trade anyway, so some kind of compromise needed to be done. Furthermore, the denser plant growth serves an important purpose in terms of creating natural hiding places for females and subdued males.

Aquarium equipment
  • Filtration: Sicce space eko 300.
  • Lighting: Twinstar 90B RGB-W.
Fish care

Areas are made in the aquarium to help create hiding places for both fry, females and subdued males. This is done by both plants, roots and by use of terrestrial vegetation.

Furthermore I have deliberately chosen to have only one species in the aquarium, which I know is not appreciated by the judges though. For this particular setup adding more fish species from the biotope would either be close to impossible or create imbalance and stress for all fish. Most species from the biotope are not commonly available in the hobby, and have simply not been possible to find.

Poecilia mexicana is possible to find, but based on my experiences with it, I have chosen not to use it. My experiences with the fish shows that the commercially bred types tends to be very aggresive towards other livebeares, and is therefore not suitable along with the somewhat quieter Xiphophorus montezumae.


  • Xiphophorus montezumae (Poeciliidae) – 6
Plant care

The plants found in the aquarium do not require special treatment. The are grown in the plant soil though.

Aquatic plants:

  • Vallisneria spiralis (Hydrocharitaceae)
  • Ceratophyllum demersum (Ceratophyllaceae)
Water care

30% of waterchange every once a week.


80 cm
35 cm
35 cm
98 L

Substrate in aquarium

Stone form
Submerged terrestrial vegetation


Comment by the expert

Michael Köck: I love the idea of a riparian aquarium and have additionally no problem with a single fish species tank, especially taking in consideration the requested functionality of the tank. However, the riparian character is not obvious with the trunk not giving the weight to the left part of the tank. The concrete structure should have covered the whole side of the tank and the Vallisneria in the back part of the aquarium disturb additionally the riparian character. Focusing witht eh structure to the left riparian part with a light counter part in the right third to give accents would have led to a more exciting composition.

Juan M. Artigas Azas: Beautiful aquarium! The first thing that came to my mind is that Vallisneria is not present in the habitat but then I read the description of the aquarium and I understood why it was used, which makes sense. As of the selection of species, I had a similar thought when Poecilia mexicana was not included in the aquarium. I understood the reasons, although it hasn’t work for me that way.

Jairo Arroyave: The BAM is beautiful and balanced, and it includes most elements present in the BIN (marginal/riverbank vegetation, aquatic plants, pebbles, sand, submerged logs), except for the diversity of fishes. However, the BAM looks more minimalistic and much more “polished” and “doctored” than the BIN. Although focusing on a single fish species was purportedly done intentionally, IMO the BAM would have benefited from including a larger portion of the fish diversity, and therefore being a more accurate representation of the BIN. Regarding lack of accuracy, Vallisneria spiralis (Hydrocharitaceae) was not described as present in the BIN but it is in the BAM. The photos and video are of excellent quality.