Apistogramma borellii

Borelli's Dwarf Cichlid is a charming and relatively peaceful small fish from South America, making it a wonderful choice for those new to cichlids. Often called the Yellow Dwarf Cichlid, its most striking feature is the male's vibrant coloration, a mix of iridescent blue and bright yellow, which becomes even more intense during courtship. He also has a magnificent, high dorsal fin which he fans out like an umbrella to impress females or ward off rivals, giving it another common name: the Umbrella Cichlid. Females are typically smaller with more subdued tones, but they transform to a brilliant lemon yellow when caring for their eggs and fry.

In your aquarium, they appreciate a setup that mimics their natural-world home. This means a tank with soft, sandy substrate for them to sift through and plenty of hiding places created by driftwood, small caves, and dense plantings. They feel most secure with this cover. For tank mates, choose other small, peaceful species that swim in the upper parts of the aquarium, such as small tetras, rasboras, or pencilfish. It's best to avoid keeping more than one male unless the tank is very large. A varied diet is essential for their health and color; they eagerly accept high-quality sinking pellets, supplemented with treats like frozen or live brine shrimp and daphnia. They are a captivating fish with interesting behaviors that are a joy to observe.

Apistogramma borellii, known as Borelli's Dwarf Cichlid, is a captivating species hailing from the cooler, slow-moving waters of the Paraguay and lower Paraná river basins in South America. Its natural habitat, which includes both clearwater and blackwater environments, explains its adaptability to a relatively broad range of pH and hardness levels in the aquarium. To truly see this species thrive, replicating a biotope is highly recommended. This involves using a fine sand substrate, which facilitates their natural sifting behavior, and incorporating an abundance of structural elements like tangled driftwood, botanical leaf litter (such as catappa or oak leaves), and small caves or ceramic pots. These structures not only provide essential hiding places but also break lines of sight, which is crucial for managing their territorial nature. The tannins released by botanicals can help acidify the water slightly, mimicking blackwater conditions and often enhancing their coloration and encouraging breeding.

Socially, A. borellii is considered one of the more peaceful Apistogramma species. A single pair can be housed comfortably in a smaller setup, but for larger tanks, a harem arrangement (one male with multiple females) is possible. This requires a spacious environment where each female can establish her own small territory centered around a potential spawning site. Keeping multiple males is ill-advised unless the aquarium is exceptionally large and intricately aquascaped.

Breeding provides a fascinating insight into their behavior. These are secretive cave-spawners. The female selects a secluded crevice or cave, lays her adhesive eggs, and provides all the direct parental care. During this period, her coloration changes dramatically to an intense, vibrant yellow—a clear signal of her maternal status, used to warn off any intruders. The male’s role is to defend the larger territory surrounding the female’s nesting site. For successful spawning and fry-rearing, stable water parameters are key; a slight drop in temperature and pH can sometimes act as a trigger, simulating the onset of the rainy season. Fry are minuscule and require microscopic foods like infusoria or vinegar eels for the first few days before they can graduate to newly hatched brine shrimp.

Their omnivorous diet in the wild consists of micro-crustaceans, algae, and detritus. In captivity, this should be replicated with a high-quality, protein-rich sinking pellet or flake, regularly supplemented with frozen and live foods like daphnia, brine shrimp, and bloodworms. This varied diet is paramount for conditioning fish for breeding and ensuring they display their best colors. Their low metabolic rate and waste production mean they contribute a smaller bioload than many other fish of a similar size, making them a good choice for a well-balanced community or species setup.

Apistogramma borellii, described by Regan in 1906, is a member of the Cichlidae family situated within the A. borellii species complex. The specific epithet honors its discoverer, Dr. Alfredo Borelli. This species exhibits pronounced sexual dimorphism and dichromatism. Males are significantly larger, developing extended soft rays on the dorsal, anal, and pelvic fins, and displaying a lyrate caudal fin upon maturation. Their coloration is a complex mosaic of metallic blues and yellows. Females are smaller, more cryptically colored, but undergo a dramatic chromatic transformation to a conspicuous vibrant yellow during the parental phase, a classic example of aposematism in substrate-spawning cichlids.

Its biogeographical range is centered in subtropical South America, specifically the drainages of the Rio Paraguai and the middle Rio Paraná in Brazil, Paraguay, and Argentina. This southerly distribution accounts for its tolerance to a cooler temperature range (20-25°C) compared to its more equatorial congeners. Ecologically, it inhabits lentic environments such as marginal lagoons, pools, and slow-flowing streams characterized by dense vegetation and substrates of sand or detritus. Its adaptability to a pH spanning from 6.0 to 8.0 reflects the seasonal fluctuations in its native water bodies.

Reproductive strategy is classified as polygynous harem-defense. Males establish and defend large territories that may encompass the smaller breeding territories of several females. Following courtship displays, characterized by the male's lateral presentations and fin erection, the female deposits adhesive eggs on the ceiling of a selected cave or crevice. She provides exclusive maternal care, including egg-fanning, hygiene, and defense, while the male patrols the perimeter. The low metabolic rate and resulting low oxygen consumption and waste production (bioload factor of 1.8) are adaptations to its niche as a benthic micro-predator in typically low-energy systems. Its diet in situ consists of invertebrates and organic detritus sifted from the substrate, a behavior that should be accommodated in captive husbandry through fine-grained substrates and appropriate food delivery methods. IUCN status is Not Evaluated (NE), but it is widespread and not considered to be under immediate threat.