Altolamprologus compressiceps 'Shell' Sumbu

The shell form of Altolamprologus compressiceps from Sumbu is a naturally occurring dwarf variant that has evolved to exploit large empty Neothauma tanganyicense shells as spawning chambers. Its extremely laterally compressed body — the defining feature of the genus — allows the fish to slide sideways through the narrow shell aperture and deposit eggs inside, far beyond the reach of egg predators.

Males are considerably larger than females (up to twice the body length) and defend a territory containing the shells of one or more females. Courtship is prolonged and involves the male hovering at the shell entrance and nudging the female. Once the bond is established the female spawns inside the shell and tends the eggs alone, while the male patrols the outer perimeter.

Despite its association with shells, this Altolamprologus is a true hunter — it preys on invertebrates and small fish fry in the wild. In captivity it should be offered protein-rich frozen foods such as Mysis and Artemia alongside a quality carnivore pellet. Water must be hard, alkaline, and impeccably clean; the species is sensitive to organic waste accumulation.

Water: pH 7.8–9.0, GH 12–20, KH 8–16, temperature 24–27 °C; very low nitrates required. Tank: 60 L for a pair; fine sand; large Neothauma-sized shells; some rockwork. Feeding: Frozen Mysis, Artemia, small Bloodworm; carnivore pellets; twice daily. Breeding: Female spawns inside large shell; male guards externally; fry accept Artemia nauplii. Compatibility: Keep as a pair; compatible with open-water Cyprichromis; avoid small fish that may be eaten.