fish · Cichlidae

Malawi compressiceps

Dimidiochromis compressiceps

Wild range: Eastern Africa: endemic to the Lake Malawi basin — lake-wide in Lake Malawi, plus Lake Malombe and the upper Shire River (FishBase; IUCN Konings et al. 2018/2019; Aquarist Atlas). (Africa)

Husbandry parameters

Difficulty: intermediate
Adult size: 20.00–25.00 cm
Min tank: 125.0 gal / 473.0 L
Temperature: 24.0–28.0°C
pH: 7.5–8.6
GH: 10.0–19.0 dGH
Flow: gentle
Water: freshwater
Temperament: semi-aggressive
Diet: carnivore
Swimming: mid
Schooling: No
Min group: 3
Community: No
Nano: No
Lifespan: 8.0–15.0 yr
Reproduction: Polygamous maternal mouthbrooder. A dominant male turns metallic blue, digs a shallow pit in the sand (often among Vallisneria, or by a rock or log) and courts ripe females. The female lays eggs in batches, picks them up, and fertilises them by mouthing the egg-spots on the male's anal fin; external fertilisation of some eggs has also been recorded. She broods about 30–100 eggs (up to ~250 reported) for roughly 3–4 weeks without eating, then releases large fry (>1 cm) that take Artemia nauplii straight away. Holding females are known to spit broods early if stressed or moved (Seriously Fish; AquaInfo; Aqua-Fish; Aquarist Atlas; Fishkeeping News).
Biotope: Shallow, vegetated, sediment-rich bays and sandy shores of Lake Malawi, especially dense Vallisneria beds (typically ~1–10 m), where it hangs head-down to ambush small fish; a golden population also lives over rock at Chizumulu Island / Linganjala Reef. Also in Lake Malombe and the upper Shire River (FishBase; Aquarist Atlas; malawi.si; Aquarium Glaser).
Countries: Malawi, Mozambique, Tanzania
IUCN: Least Concern

At a glance: Malawi compressiceps care

Compiled reference information. Review the care notes and original sources below.

What temperature is listed for Malawi compressiceps?

The compiled profile lists 24.0–28.0 °C for Malawi compressiceps (Dimidiochromis compressiceps). Check the original sources below for context and differing recommendations.

What tank size is listed for Malawi compressiceps?

The profile lists a minimum tank volume of 125.0 US gallons (473.0 liters). Volume alone does not establish suitability; consider dimensions, group size and other inhabitants alongside the full care notes.

What pH is listed for Malawi compressiceps?

The compiled profile lists a pH of 7.5–8.6. Review the cited care sources alongside the other water parameters in this profile.

Natural habitat

A large, knife-thin Lake Malawi haplochromine predator, the Malawi eye-biter. Its head and body are extremely compressed side to side, so it almost disappears when seen head-on among Vallisneria. It ambushes small fish (mostly juvenile utaka), swallowing them whole and tail-first. Females and non-breeding males are silver with a dark stripe from snout to tail; dominant males flush metallic blue with orange-red fin edges and egg-spots. Despite the name, eye-eating is rare in the wild.

Where they are found

Catalog primary Dimidiochromis compressiceps (Boulenger, 1908) — ITIS TSN 649015 valid (author (Boulenger, 1908)), GBIF 2369877 accepted, FishBase, Wikipedia; parentheses because it was described as Paratilapia compressiceps Boulenger, 1908 (holotype BMNH 1908.10.27.59, Lake Nyasa). Later placed in Haplochromis (most older aquarium literature: 'Haplochromis compressiceps') and Cyrtocara (ITIS TSN 169928, invalid → D. compressiceps), then in Dimidiochromis Eccles & Trewavas, 1989. Synonyms Paratilapia compressiceps, Haplochromis compressiceps and Cyrtocara compressiceps are recorded in aliases under Scott's naming rule. Not to be confused with the Lake Tanganyika Altolamprologus compressiceps (this catalog's `compressiceps` row; ~12–15 cm, a different genus and lake), which shares the epithet. Lookalike caution: the congener Dimidiochromis strigatus is similar but less compressed, with more green in males and a red patch behind the pectoral fin. It is sometimes sold as compressiceps, and the two hybridise. OB (orange-blotch) fish sold as compressiceps are hybrids, and albino forms are aquarium-bred (Aquarist Atlas). The common name comes from Wickler's 1966 report of fish eyes in wild stomach contents; this has not been confirmed as normal wild behaviour (Konings; Aquarium Glaser). IUCN Least Concern (Konings, Kazembe, Makocho & Mailosi; assessed 22 June 2018, amended 2019). Trade names: Malawi eye-biter, Malawi eyebiter, Eye-biter, Haplochromis compressiceps, Malawi compressiceps.

Aquarium care

Plan at least 125 US gal / ~475 L with a footprint of 150 cm (5 ft) or more (Guidarium 475 L / 150 cm; Aqua-Fish 500 L / ≥150 cm; Aquarium Store Depot 125 gal). Prefer a 6 ft / 180 cm tank of 150–180+ gal (malawi.si 600 L / 180 cm; AquaInfo 200 cm minimum length; Aquarist Atlas 180 gal) for adults or a mixed hap tank. Seriously Fish's 150 cm / ~250 L base is the low end for juveniles or a small group only. Temperature 24–28°C (Aquarium Glaser, Aquarist Atlas, FishBase 22–28, Seriously Fish 23–28, AquaInfo 22–28; Aqua-Fish 24–27). pH 7.5–8.6, never below 7.5 for long (Aquarium Glaser; Seriously Fish 7.5–8.8; AquaInfo 7.5–8.5; Aqua-Fish/Guidarium 7.8–8.6). GH 10–19 dGH (FishBase/Aqua-Fish 9–19; Seriously Fish/Guidarium 10–25; AquaInfo 12–16). Use a sand substrate, dense Vallisneria stands for ambush cover, and only sparing rockwork, leaving long open swimming lanes. Gentle to moderate flow with strong filtration (Seriously Fish: no strong current; Aqua-Fish/Guidarium: moderate). A tight lid is advisable. Intermediate difficulty: hardy and easy to feed, but space-hungry and predatory.

Feeding

Wild fish are ambush piscivores, mainly taking juvenile utaka and other small shoaling cichlids, with fry and invertebrates as extras (FishBase trophic level ~4.2; Aquarist Atlas; malawi.si). Captive fish train readily onto dead foods: offer large carnivore/cichlid pellets or sticks plus frozen mysis, krill, chopped prawn, mussel, cockle and lancefish. Rotate foods, since some keepers report refusal after several days of the same item (Seriously Fish; Aqua-Fish; Aquarium Glaser; AquaInfo). Pellets should not be the sole diet. Avoid routine live feeder fish (disease risk) and fatty mammalian meat. Feed modest meals 1–2× daily. Food must usually be moving; items left on the bottom are often ignored (AquaInfo).

Compatibility

A predator that is fairly peaceful toward fish too big to swallow, but it will eat anything that fits in its very large mouth. Avoid tankmates under ~12–13 cm (5 in) and any juveniles or fry (Seriously Fish; Aquarium Glaser; Aqua-Fish). Best with calm, large Malawi haps and utaka (e.g. Nimbochromis, Cyrtocara moorii, Protomelas, Copadichromis, Sciaenochromis) or large Synodontis. Avoid hectic mbuna: they stress this slow ambusher, and keepers report compressiceps losing fights with aggressive mbuna (Aquarium Glaser; Aquarist Atlas; Fishkeeping News). Keep only one adult male per tank, with several females. Breeding males become territorial and can batter weaker fish in small tanks, while crowding in a large tank diffuses this (Fishkeeping News). Some keepers report occasional eye-nipping of tankmates in aquaria. Do not mix with D. strigatus (hybridisation). Not community-safe.

Breeding

Breeds in large tanks (≥150 cm) as one male with 3–6 females, which spreads the male's harassment (Seriously Fish; Aqua-Fish 2–3 females; malawi.si). Condition at pH 8.0–8.5 and 25–27°C (Seriously Fish). Females incubate for ~3–4 weeks (~23 days at 24°C, AquaInfo) and often release 40–70 fry. Strip only if experienced, as females spit early when stressed. A female kept away from the group too long may lose rank. Keep separate from D. strigatus to avoid hybrids (Aquarist Atlas).

Sources

Compiled from multiple independent care sheets — not copied from a single site.