Amatitlania nigrofasiata

The Convict Cichlid, also known as the Zebra Cichlid, is a popular fish from Central America, well-known for its striking personality. Growing to about 10-15 cm, it requires a freshwater aquarium of at least 80 liters to provide adequate space. These are active fish that primarily inhabit the middle and bottom levels of the tank. They are quite hardy, thriving in a range of water conditions, including temperatures between 24 and 28 degrees Celsius and a broad pH spectrum.

As omnivores, they are not picky eaters and will readily accept a variety of common fish foods like flakes and pellets, which should be offered daily. One of their most notorious behaviors is digging in the substrate and uprooting plants, so it's wise to choose robust plants or opt for a setup with rocks and wood instead. While their care is rated as medium difficulty, this is mainly due to their territorial nature. They can be aggressive towards tank mates, especially in smaller spaces or when breeding, which they do very easily. Their high waste output also means that good filtration and regular water changes are essential to keep them healthy for their potential 10-year lifespan.

The Convict Cichlid, Amatitlania nigrofasciata, is a cornerstone species in the aquarium hobby, hailing from the freshwater rivers and lakes of Central America. Its adaptability and assertive demeanor make it a fascinating, albeit challenging, subject for many aquarists. To properly house this species, an aquarium of no less than 80 liters is fundamental to mitigate its inherent territoriality. As they mature to a full size of 10-15 cm, their need for personal space increases, particularly for a breeding pair.

Water chemistry is thankfully flexible, accommodating a pH between 6.5 and 8.0 and hardness from 90 to 350 ppm. However, maintaining stable temperatures between 24-28°C is crucial for long-term health. Low-flow water conditions are preferred, mimicking the slower-moving waters of their natural habitat. A key behavioral trait to plan for is their tendency to be a 'plant rooter'. They will actively re-scape the aquarium by digging, which makes delicate or shallow-rooted plants unsuitable. Hobbyists should opt for durable species like Anubias or Java Fern attached to driftwood or rocks, or embrace a hardscape-focused environment with plenty of caves and structures that also serve as territorial markers.

Physiologically, the Convict Cichlid has a medium metabolism and is very active, requiring daily feedings of a varied, omnivorous diet. High-quality pellets and flakes should form the staple, supplemented with frozen or live foods to encourage natural foraging behaviors and optimal health. One of the most significant considerations for keeping this species is its high waste production, indicated by a substantial bioload factor. This necessitates a powerful and efficient filtration system (e.g., a canister filter or large hang-on-back) and a rigorous maintenance schedule with regular water changes to prevent the accumulation of nitrates. Their territoriality means tank mates must be chosen with extreme care; they should be robust, of similar size, and able to hold their own. Small, timid fish will be bullied relentlessly. Finally, their prolific and straightforward breeding is a major characteristic. A conditioned pair will readily spawn, displaying remarkable parental care by fiercely guarding their eggs and fry, transforming a section of the tank into a no-go zone for all other inhabitants.

Amatitlania nigrofasciata, belonging to the family Cichlidae, is a neotropical freshwater species endemic to Central America. Its taxonomic classification places it within the order Cichliformes, a diverse group known for complex social behaviors. Its common name, Convict Cichlid, is derived from its vertical black bars on a grayish-blue body, while the synonym Zebra Cichlid also alludes to this pattern. The species exhibits a notable tolerance to a range of hydrochemical conditions, a factor contributing to its IUCN status of 'Least Concern' (LC). It thrives in a pH range of 6.5 to 8.0 and water hardness spanning 90-350 ppm (approximately 5-20 dGH), with optimal TDS levels around 250 ppm. This adaptability allows it to inhabit various biotopes, from flowing rivers to stiller lake environments, although captive specimens show a preference for low-flow conditions.

A. nigrofasciata is a benthopelagic omnivore, occupying the middle and bottom strata of the water column. In situ, its diet consists of small invertebrates, algae, and detritus. In ex-situ environments, it accepts a wide array of prepared and live foods. Its physiology is characterized by a medium metabolic rate and moderate oxygen consumption, yet it produces a significant amount of nitrogenous waste, as quantified by a high bioload factor (5.5). This necessitates robust biological filtration in closed aquatic systems to manage the nitrogen cycle effectively. Behaviorally, it is highly territorial and engages in substrate modification ('plant rooter'), which is often a precursor to spawning activity. Reproduction is uncomplicated; it is a biparental, substrate-spawning species. Pairs form strong bonds and exhibit advanced parental care, defending their spawning site and fry aggressively. This pronounced territoriality is a dominant factor in its social dynamics and requires careful consideration in community aquaria.