Gladicauda Checkerboard Cichlid (Dicrossus gladicauda)

Geographic Origin and Biotope: Colombia, restricted to the Rio Atabapo basin. Very dark water streams (Blackwater), acidic, shady, overflowing with submerged timber and sandy quartz bottoms covered with leaves.

Taxonomy and Morphology: Swordtail Checkerboard Cichlid (Dicrossus gladicauda). Takes its common and Latin name ("gladicauda" = sword tail) from the male's tail, which develops a single long asymmetrical filament in the upper lobe, like a sword.

Social Behavior: Peaceful, but males are competitive in cramped tanks. They live mostly sifting the substrate on their own. Ideally, 1 male and several females or schools of juveniles are recommended.

Coloration and Sexual Dimorphism: Males (spectacular) have 2 parallel rows of square black spots, reddish reflections on the anal and dorsal fins and the iconic asymmetric blue/red "sword" on the tail. Simpler females, with 3 prominent black spots.

Aquarium Setup: The water must be the color of dark tea (intense tannins). Very white sand, Indian almond leaves (Catappa) and an immense interweaving of woods. Any intense light must be shielded with Limnobium.

Diet and Feeding: Feeding rhythms are slow. Provide live (brine shrimp nauplii, Moina) and very small frozen food. Tends to ignore classic dry feeds for days during acclimatization.

Water Quality: Zero chemical tolerance. To see its colors the water must have a total hardness of less than 2-3 dGH and a pH well below 6.0 (the target is 5.0). Tolerated Nitrites/Nitrates = ZERO.

Compatibility and Tankmates: Compatible only with tiny schooling characins from black waters that tolerate the same extreme care (e.g. small Nannostomus). Absolutely forbidden turbulent Loricariids or Corydoras.

Aquarium Reproduction: Rarely reported. Lowering the values (pH to 4.5 and very low TDS) stimulates courtship. They lay on a leaf on the bottom fiercely protected by the tiny female.

Risks and Diseases: Dropsy from stress and bloat if overfed with tubifex or foods rich in polluted blood. Very high loss rate in the first 15 days after transport (imported fish).