Aquarium Setup: The aquarium architecture MUST flawlessly accommodate their endless energy and hyper-prolific breeding. A minimum 60-liter (15-gallon) tank (at least 60 cm long) is required. The absolute most critical requirement is overwhelming, impenetrable thickets of fine-leaved vegetation (like Guppy Grass, Hornwort, or Java Moss) to provide exhausted females a place to hide from relentless male harassment, and to offer the massive quantities of fry a chance to survive. The water flow MUST be gentle; they are clumsy swimmers and will struggle in powerful currents.
Diet and Feeding: They are highly active, voracious omnivores that act as excellent scavengers and algae grazers. In the aquarium, they possess a massive, bottomless appetite and are the ultimate beginner-friendly eaters. They will aggressively accept absolutely any commercial diet. However, to maintain perfect health and prevent severe digestive issues, their diet MUST be heavily skewed toward vegetable matter. Daily offerings of spirulina-based flakes or blanched vegetables (zucchini, peas) are mandatory, supplemented 2-3 times a week with meaty foods (bloodworms, Artemia) for protein.
Water Quality: Originating from harsh, alkaline Central American swamps, they strictly demand highly stable, intensely clean, and moderately hard water. They thrive in warm tropical temperatures (24-27°C / 75-81°F). Crucially, they strictly require moderately hard to very hard water (GH 10-25) and a distinctly alkaline pH (7.0 - 8.2). They will rapidly suffer severe physiological collapse, clamped fins, and lethal bacterial infections if kept in soft, acidic water (like Amazonian blackwater). Rigorous weekly water changes (30-50%) are unconditionally mandatory due to their massive bioload.
Compatibility and Cohabitation: Compatibility is absolutely excellent, provided tankmates share their strict requirement for hard, alkaline water. They are the perfect, vibrant centerpiece for a peaceful, hard-water community biotope. Excellent companions include fast-swimming Zebra Danios, peaceful Tetras tolerant of hard water, Corydoras, and other livebearers (Mollies, Guppies). They MUST NEVER be housed with aggressive fin-nippers (like Tiger Barbs) that will shred their fins, nor with large predatory Cichlids. NOTE: They will readily hybridize with Swordtails (Xiphophorus hellerii).
Aquarium Breeding: Breeding is utterly explosive, inevitable, and completely unstoppable. They are highly prolific livebearers; males use their gonopodium to internally fertilize the female. Females can store sperm for months. Following a 4-week gestation (indicated by a massive, swollen belly and dark "gravid spot" near the anal fin), the female will drop 20-50 massive, fully formed, free-swimming fry. The adults are relentless fry-eaters; the tank MUST contain massive, dense tangles of floating plants for the fry to hide, or pregnant females must be moved to a breeding trap.
Risks and Diseases: The absolute greatest physical risk is severe physiological collapse and rapid death caused by keeping them in soft, acidic water; hard, alkaline water is strictly, unconditionally mandatory. The second major risk is lethal exhaustion and stress for females caused by housing too many males; the 3-to-1 female-to-male ratio is absolutely critical to disperse harassment. Finally, without dense vegetation, 100% of the fry will be cannibalized within hours of birth.