Altolamprologus calvus

Altolamprologus calvus is one of the most architecturally distinctive cichlids from Lake Tanganyika, possessing a dramatically laterally compressed body with a very steep forehead profile. This unique body shape allows it to wedge into narrow rock crevices to ambush prey — primarily small fish and invertebrates. The body is covered in rows of pearlescent spots on a dark background, creating a striking appearance that improves with age. Multiple color variants exist, including the classic black calvus and the white or yellow calvus from different lake regions. In the wild, calvus is a slow, deliberate predator, drifting near rock faces before lunging at unsuspecting prey. In the aquarium, it is a peaceful species when not feeding and will largely ignore tankmates it cannot consume. Its laterally flattened profile makes it unable to swallow large prey. Altolamprologus calvus is a cave spawner that lays adhesive eggs on cave walls and surfaces. Both parents participate in brood care, though the female bears the primary responsibility for egg tending. This species grows slowly and reaches sexual maturity later than most cichlids; its long lifespan of 10–15 years rewards keepers willing to invest time and proper care.

Tank Setup A 100-liter aquarium suits a pair or a small harem group. Create a heavily rock-scaped environment with narrow crevices and overhangs that mirror Lake Tanganyika's rocky habitat. This species is a skilled navigator of tight spaces and will use such structures extensively. Sandy substrate is preferred.

Water Parameters Maintain pH 7.5–9.0, temperature 23–26°C, and hard alkaline water. Calvus is relatively hardy once established and tolerates stable Tanganyika parameters well. Perform 20–25% weekly water changes.

Filtration A quality canister filter providing moderate turnover is adequate. Good biological filtration is essential as this species is sensitive to ammonia and nitrite spikes. Mechanical filtration should be maintained to prevent clogging.

Diet Feed frozen or live foods: brine shrimp, mysis shrimp, small feeder shrimp, and carnivore pellets. This species is a picky eater and may refuse dry foods initially; wean onto pellets gradually using live foods as incentive. Feed once daily.

Tankmates Excellent tankmates include shell dwellers, Julidochromis species, and larger Synodontis catfish. Any fish small enough to be swallowed will be consumed, so choose tankmates accordingly. Generally peaceful toward fish it cannot predate.

Breeding Spawning occurs in narrow crevices or caves. Females tend eggs while males guard the wider territory. Clutches of 50–150 eggs take 2–3 days to hatch. Fry are slow to develop and benefit from baby brine shrimp and micro-worms once free-swimming.