Vieja hartwegi (Rio Grijalva)

This locale form of Vieja hartwegi from the Rio Grijalva drainage in Chiapas, Mexico is particularly sought after by collectors for its exceptional coloration. Where standard V. hartwegi populations show variable orange-red marking, the Rio Grijalva form exhibits markedly more intense and extensive orange-red suffusion across the posterior body, dorsal fin, and caudal fin, creating a stunning bicolor effect in dominant males.

All aspects of care, temperament, and breeding behavior follow the standard V. hartwegi description — this is a locale-specific variant rather than a distinct species. The distinction is primarily of interest to hobbyists engaged in geographically accurate Central American biotope aquarium projects or breeding programs that track regional genetics.

Hobbyists maintaining this form should keep records of origin to preserve locale purity when breeding, as mixing with other V. hartwegi populations reduces the distinctiveness of the Rio Grijalva coloration in subsequent generations.

Water: 24–28°C, pH 7.0–8.0, GH 8–18, KH 4–12; stable conditions; weekly 25–30% water changes. Tank: 400 L minimum; rocky biotope with Chiapas-style decor; sandy substrate; driftwood optional. Feeding: Omnivore — quality cichlid pellets, earthworms, shrimp; supplement with vegetable matter. Breeding: Substrate spawner; track locale origin in records; biparental care; aggressive defense. Compatibility: Large robust CA cichlids; best kept with other Usumacinta-Grijalva species for biotope accuracy.