Apistogramma borellii Opal Care Guide - Aquarium Setup, Diet & Breeding

Apistogramma borellii opal is a selectively bred colour form of the yellow dwarf cichlid, valued for its blue-white, opalescent body markings and warm yellow colouring. Mature males are larger and usually develop more extended dorsal, anal and tail fins, while females are smaller and can become especially vivid yellow when breeding or defending a brood.

These fish are intelligent, expressive and full of personality for their size. They spend much of their time exploring the lower levels of the aquarium, inspecting caves and leaf litter, and displaying to their mate or rivals. Although generally less combative than many larger cichlids, they become strongly territorial around a spawning site.

In nature, Apistogramma borellii inhabits slow-moving streams, lagoons, marshes and quiet margins of larger rivers. Such habitats often contain submerged wood, leaf litter and dense marginal vegetation, creating a complex network of shaded retreats and feeding areas.

The species is notable among Apistogramma for its tolerance of cooler conditions and its ability to occur in habitats with marked seasonal changes. The opal variety retains the compact body shape and characteristic dwarf-cichlid behaviour of the wild form while displaying a brighter, more reflective aquarium colouration.

Apistogramma borellii is native to the subtropical freshwater habitats of central South America, particularly the Paraná and Paraguay river systems in Argentina, Paraguay and southern Brazil. The opal form is a selectively maintained aquarium colour variety rather than a separate wild species.

A pair should have at least a 60-litre aquarium, with a footprint of approximately 60 by 30 cm; a larger tank is preferable for a community or harem arrangement. Use fine sand or another smooth substrate, along with driftwood, leaf litter, hardy plants and several caves or shaded shelters. Dense visual barriers help divide territories, while gentle filtration, subdued lighting and open areas for foraging recreate the calm, structured habitats this species favours.

Males reach a maximum of about 7.5 cm (3 inches), while females usually remain smaller at around 4.5–5 cm (1.8–2 inches).

Offer a varied diet based on quality small cichlid pellets or granules, supplemented with frozen or live foods such as brine shrimp, daphnia, bloodworm and blackworm. They naturally pick through the substrate for small crustaceans and other invertebrates, so sinking foods are useful. Feed small portions once or twice daily and remove uneaten food promptly.

Apistogramma borellii opal can be kept with peaceful, similarly sized community fish such as small tetras, pencilfish, rasboras, peaceful danios, hatchetfish and small Corydoras. They are best avoided with aggressive cichlids, boisterous fin-nippers and large predatory fish. Keep an eye on territorial behaviour in small aquariums, especially when a female is guarding eggs or fry; multiple males should only be housed together in a spacious, heavily structured tank.

Apistogramma borellii opal are cave-spawning dwarf cichlids. Provide a small cave, coconut shell or overturned pot, and condition a compatible pair with varied, protein-rich foods. The female usually lays around 20–80 eggs on the cave roof and guards the eggs and free-swimming fry, while the male defends the surrounding territory. Eggs typically hatch in two to four days, with fry becoming free-swimming a few days later. Feed the young newly hatched brine shrimp, microworms or another suitably tiny food.

Males are larger and generally show longer, more pointed dorsal, anal and caudal fins, with stronger blue and yellow patterning. Females are shorter-bodied, more rounded and often turn bright yellow when breeding, while their fins are less extended.