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No federal permit to keep

Masked julie

Julidochromis transcriptus

Fishes › Cichlids (Cichliformes) › Cichlidae (Cichlids)

The masked julie (Julidochromis transcriptus) is a species of cichlid endemic to Lake Tanganyika in Africa where it is found only along the northwestern shore preferring areas with rocky substrates.

Aquarium hobby

Experience: Intermediate

FamilyCichlids

Adult lengthup to 2.8 in

WaterFreshwater

HabitatLives in freshwater

Care at a glance

Species-specific aquarium care

Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 2.8 in / 7 cm).
Water: Freshwater.
Temperature: 72–77°F (range recorded for this species).
pH: 8.5–9.2.
Hardness: 8–14 dGH.
Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
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

Behaviour: in a pair; not a community fish.
Difficulty: Moderate (Seriously Fish rating).

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 Tanganyika cichlids

Applies to most species in this group. Habitat: Rocky reefs, shell beds and sand of Lake Tanganyika. Individual species can differ, so compare with the species numbers above and the linked sources.

Housing & setup

Use species-specific alkaline-water parameters and stable, well-oxygenated conditions. For N. multifasciatus, Seriously Fish gives pH 7.5–9.0 and general hardness 8–25 dGH.
Shell-dwellers need beds of empty snail shells; rock-dwellers like Julidochromis need stacked rockwork; Tropheus need large groups and spacious tanks.

Sources 117 119 164 118 256 273

Climate & lighting

Water

76–81°F

Sources 117 119 164 118 256 273

Diet

Tropheus moorii needs a vegetable-based staple with small suitable live/frozen supplements. Other Tanganyikans need their own feeding plan; shell-dweller and predator diets differ.

Sources 117 119 164 118 256 273

Social life

Often pair- or colony-forming and territorial; research each genus.

Sources 117 119 164 118 256 273

Health watch

Tropheus are prone to bloat on rich foods; sudden water changes stress Tanganyikans.

Sources 117 119 164 118 256 273

Understanding the animal

About this animal

They eat zooplankton and benthic invertebrates found in the algae growth in the wild.

Quoted from the Wikipedia article “Masked julie” (CC BY-SA 4.0) 174

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. Uses both the bottom and open water. Rock-dwelling. Usually solitary, territorial. Feeds on microorganisms.
Water it lives in	Freshwater, 72–77 °F (22–25 °C), pH 8.5–9.2, hardness 8–14 dH.
Climate	Tropical climate.
Wild diet	Hunting macrofauna (predator).
Behavior to plan for	Breeding: clutch tenders.

What this means for care

Keep water within its wild range, 72–77 °F.

FishBase species summary: Julidochromis transcriptus

Native climate (measured)

Warm-season highs	about 85°F (up to 88°F in the hottest sampled areas)
Cool-season lows	about 59°F (down to 43°F in the coldest sampled areas)
Average temperature	62–77°F across sampled records
Relative humidity	58–72% on average (driest month about 60%)
Rainfall	about 1057 mm a year

Measured at 5 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.

Overview	The masked julie (Julidochromis transcriptus) is a species of cichlid endemic to Lake Tanganyika in Africa where it is found only along the northwestern shore preferring areas with rocky substrates. They eat zooplankton and benthic invertebrates found in the algae growth in the wild. This species reaches a length of 7 cm TL. — Wikipedia (community-edited)
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	Usually solitary, territorial. Feeds on microorganisms. Aquarium keeping: in pairs; minimum aquarium size 60 cm. — 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 sources2.7in

FishBase 1642.8

Seriously Fish species profiles 1672.6

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

Water temperature

Reported72–77°F

FishBase 16472–77

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

pH

Reported8.5–9.2

FishBase 1648.5–9.2

Water hardness

Reported8–14dGH

FishBase 1648–14

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)
11 iNaturalist observations of captive animals

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 — Neolamprologus multifasciatus Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
Seriously Fish — Tropheus moorii 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.
iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.