Orinoco Cupid Cichlid (Biotodoma wavrini)

Geographic Origin and Biotope: Limited to the upper Orinoco River basin in Colombia and Venezuela. Populates slow or moderate flowing rivers, grouping near sheltered banks where huge submerged roots offer shelter.

Taxonomy and Morphology: Orinoco Cupid Cichlid (Biotodoma wavrini). Closely related to B. cupido. Distinguished by its slightly more elongated body and because the dark line dividing the eye continues towards the operculum more markedly. The lateral spot (ocellus) is often located higher on the back.

Social Behavior: Like B. cupido, it is a peaceful and highly gregarious Cichlid that needs the company of at least 5-6 conspecifics. Single specimens waste away from stress. Moderately shy, spends its time inspecting the bottom.

Coloration and Sexual Dimorphism: Silvery or pale golden base with a slight vertical bar under the ocellus. In perfect conditions it shows off pastel blue and green reflections. The sexes are virtually identical (except when inspecting the genital papillae during the mating season).

Aquarium Setup: Minimum 120 cm (48 inches) for a group. An expanse of pure, soft sand is unparalleled for their comfort. Decorate with twisted woods and a thick blanket of Catappa leaves. Lighting should not be blinding.

Diet and Feeding: Occasional Eartheater. Will swallow mouthfuls of sand to expel it from the gills, sifting microscopic crustaceans. In captivity, provide Daphnia, bloodworms and fine-caliber, high-protein bottom pellets.

Water Quality: Very delicate species: tolerates only exceptionally soft waters (often measurable in microSiemens) and decidedly acidic. Even a modest accumulation of nitrates will cause labored breathing, loss of appetite and rapid decline.

Compatibility and Tankmates: Shares the habitat perfectly with Cardinals, warm-water Corydoras (e.g. C. sterbai), and small loricariids. Totally incompatible with large territorial Cichlids or more active and large Eartheaters (e.g. Satanoperca or Geophagus).

Aquarium Reproduction: Rare and difficult. They lay on previously cleaned stones or large leaves. They form stable pairs during mating and defend (in a non-lethal but determined way) the nest area and the fry.

Risks and Diseases: Suffers enormously from intestinal pathogens if fed improperly or kept in poor water. The sand must not be sharp otherwise damage to the gills causes lethal bacterial infections.