Fenestratum Cichlid Care Guide - Tank Setup, Diet & Breeding

The Fenestratum Cichlid is a large, powerful Central American cichlid with a deep body, prominent head, and strong jaws. Its coloration varies with locality, age, and mood, but mature fish may display green, blue, yellow, orange, or reddish tones over a dark or mottled base. The flanks can show iridescent markings and broken vertical patterning, while the fins often carry contrasting spots or edging.

This species is intelligent, active, and confident, spending much of its time examining its surroundings and rearranging parts of its territory. It can become highly assertive, particularly when mature or preparing to spawn, and its substantial size gives it the ability to intimidate or injure smaller aquarium inhabitants.

In the wild, Fenestratum Cichlids are associated with warm freshwater habitats containing submerged roots, rocks, woody debris, and areas of softer sediment. They are adaptable fish, but their natural environment provides both open swimming areas and places where a territorial pair can retreat and defend a spawning site.

Paratheraps fenestratus has sometimes been confused with similar large Central American cichlids, and its appearance can differ noticeably between collection locations. It is best regarded as a specialist species for experienced keepers who can accommodate a large, robust fish and its potentially intense territorial behaviour.

Paratheraps fenestratus is native to southern Mexico, particularly the river systems of the Pacific slope and the lower Río Usumacinta region. Its natural range lies in Central America, where it inhabits warm, slow-moving rivers, backwaters, and connected lagoons.

Allow at least 300 litres for one adult, with a larger aquarium of 500 litres or more preferable for a pair or any community arrangement. A tank around 150 cm long and 50 cm front-to-back is a practical minimum for a single adult, though more length and width are strongly recommended. Use a sturdy aquarium with efficient filtration and a secure cover, since this powerful fish produces considerable waste and may move equipment or decor. Provide a fine sand or smooth-gravel substrate, large rocks, robust bogwood, caves, and visual barriers, while leaving an open area for swimming. Anchor heavy decorations securely and avoid delicate plants, which may be uprooted or damaged.

Males can reach about 35 cm (14 in) in total length, while females are usually smaller at around 25–30 cm (10–12 in).

This omnivorous cichlid should receive a varied diet based on high-quality large cichlid pellets or granules, supplemented with prawns, mussel, earthworms, insects, and suitable frozen foods. Some vegetable matter, such as spirulina-based foods or blanched vegetables, is also beneficial. Feed moderate portions once or twice daily, removing uneaten food, and avoid relying on mammalian meat such as beef heart, which can contribute to digestive and health problems.

Fenestratum Cichlids are best kept alone, as a compatible adult pair, or in a carefully planned large Central American cichlid community. Possible companions in a very spacious aquarium include similarly sized, robust species such as Oscar cichlids, large Vieja, Amphilophus, or Parachromis species, although compatibility is never guaranteed. Avoid small peaceful fish, slow-moving species, delicate cichlids, and most community fish, as they may be bullied, injured, or eaten. Keep only one male unless the aquarium is exceptionally large and structured to divide territories.

Fenestratum Cichlids are substrate-spawning cichlids that form pairs. Provide a mature aquarium with a large flat stone, slate, or other smooth spawning surface, along with caves and visual boundaries. The female lays adhesive eggs on the chosen surface, while both parents usually defend the clutch and tend the free-swimming fry. Feed the parents generously with a varied, nutritious diet, and offer the young newly hatched brine shrimp or another appropriately sized fry food. Because adults can be strongly territorial, a bonded pair is best given a dedicated breeding setup.

Mature males are generally larger and may develop longer dorsal and anal fins, a broader head, and more pronounced nuchal growth. Females usually remain smaller and rounder-bodied, particularly when carrying eggs, although colour and fin differences vary between individuals and locality forms.