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No federal permit to keep

Haplochromis yellow black line

Mylochromis melanonotus

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The haplochromis yellow black line (Mylochromis melanonotus) is a species of cichlid fish endemic to Lake Malawi where it is usually found over sandy substrates.

Intro from Wikipedia (CC BY-SA 4.0)

Aquarium hobby

Experience: Intermediate

FamilyCichlids

Adult lengthup to 10.2 in

WaterFreshwater

HabitatLives in freshwater

Care at a glance

Species-specific aquarium care

Tank: At least 42 in long and 21 in front to back for one adult (adults commonly reach about 10.2 in / 26 cm).
Water: Freshwater.
Temperature: 75–79°F (range recorded for this species).
Layout: Lives on or near the bottom: floor space and hiding places matter more than height.
Diet: A predator: feed meaty foods sized to its mouth (frozen fish, shrimp, worms); it will eat tankmates that fit in its mouth. FishBase classes it as a carnivore.

Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.

Care guide

Species care notes

Tank: a base of at least 59 × 24 in (roughly 143 US gallons); space needed is rated “very large tank”.
Water: hard, alkaline water, 75–82 °F, pH 7.6–8.8, 10–25 dGH.
Behaviour: temperament predatory.
Difficulty: Moderate (Seriously Fish rating).

Short excerpts from the species profile:

Setup: “Arrange piles of rocks to form caves and hiding places, with areas of open space between for swimming.”
Diet: “Offer a varied diet of meaty live and frozen foods and good quality cichlid pellets.”
Tankmates: “It is piscivorous and will eat small fish.”
Breeding: “Not known to have occured in aquaria.”

From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167

Group care guide

Lake Malawi peacocks and haps

Applies to most species in this group. Habitat: Open water and sand of Lake Malawi. Individual species can differ, so compare with the species numbers above and the linked sources.

Housing & setup

Hard, alkaline water (pH 7.8–8.6), a long tank (5 ft+ for larger haps) with open sand and some rock.
Generally less aggressive than mbuna; males color up best with several females.

Sources 117 119 164 118 272

Climate & lighting

Water

76–82°F

Sources 117 119 164 118 272

Diet

For Aulonocara stuartgranti, use small prepared foods with some vegetable content and varied small live/frozen invertebrates. Match other haps to their own feeding ecology.

Sources 117 119 164 118 272

Health watch

Do not diagnose bloat from a label such as “mbuna-style food”; Aulonocara stuartgranti diets can include vegetable foods. Match food and tankmates to the species.

Sources 117 119 164 118 272

Understanding the animal

In the wild

From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.¹

Where it lives	Lives in freshwater, in lakes. Stays near the bottom. Most frequently seen over sand but may also occur in the intermediate sand-rock habitat.
Water it lives in	Freshwater, 75–79 °F (24–26 °C), depth 15–18 m.
Climate	Tropical climate.
Wild diet	Hunting macrofauna (predator).

What this means for care

Keep water within its wild range, 75–79 °F.

FishBase species summary: Mylochromis melanonotus

Native climate (measured)

Warm-season highs	about 87°F (up to 90°F in the hottest sampled areas)
Cool-season lows	about 60°F (down to 54°F in the coldest sampled areas)
Average temperature	72–76°F across sampled records
Relative humidity	67–69% on average (driest month about 55%)
Rainfall	about 1161 mm a year, with strong wet and dry seasons

Measured at 18 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.

From the sources

Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.

Where it lives	Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase
Biology	Most frequently seen over sand but may also occur in the intermediate sand-rock habitat. Usually collected from trawl hauls in shallower stations. Feeds on small fish, gastropods, and lamellibranch mollusks. — FishBase

Data and studies

The numbers

Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.

Adult length

Average of sources10.2in

FishBase 16410.2

Seriously Fish species profiles 16710.2

Maximum recorded length. Measured as total length. Fish in home aquariums often stay smaller than wild records.

Water temperature

Average of sources75–80.5°F

FishBase 16475–79

Seriously Fish species profiles 16775–82

Range the species tolerates in nature; aim for the middle.

pH

Reported7.6–8.8

Seriously Fish species profiles 1677.6–8.8

Water hardness

Reported10–25dGH

Seriously Fish species profiles 16710–25

Minimum tank footprint

Reported59in

Seriously Fish species profiles 16759

Seriously Fish recommends a tank base of at least 59 × 24 in (about 143 US gallons).

Federal legal snapshot

No federal permit to keep

No federal law singles out this species for private keepers. State and local rules still apply.

State law decides most of it. Each state sets its own permits and bans for exotic, native, venomous and dangerous animals, and cities and counties can be stricter. Find your state agency →

Not covered by the Animal Welfare Act

The Act only covers warm-blooded animals. Reptiles, amphibians, fish and invertebrates have no federal care standards, even at licensed facilities; state and local rules may still apply.

Kept in captivity?

Every species on this site needs evidence that people actually keep it. For this one:

Has a Seriously Fish aquarium species profile
FishBase records it in the aquarium trade (Aquarium=commercial; AquariumFishII=based mainly on breeding)

Sources for this sheet

FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
Seriously Fish — Aulonocara stuartgranti Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.