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Calvus

Altolamprologus calvus is a cichlid found only in the southwestern waters of Lake Tanganyika, instantly recognizable by its strikingly flattened, laterally compressed body. That slender shape lets it slip into narrow cracks between rocks, where it spends much of its time tucked away and out of sight. Calm and unhurried by nature, it does hold a sense of territory, and when a shrimp or other prey wanders past, it drifts almost lazily across the rockwork before striking in an instant, the hallmark of a patient ambush predator. Adults reach around 13 to 14 cm, and while keeping them well calls for some intermediate-level experience, their understated, wild presence in a rock-filled aquarium makes them a favorite among Lake Tanganyika cichlid keepers.

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About Calvus

Altolamprologus calvus is a laterally compressed cichlid endemic to Lake Tanganyika that ambushes prey from rocky crevices. Explore its care essentials, adult size of 13-14cm, and key points to know before bringing one home.

7 things to know before welcoming a Calvus

  1. 1Rockwork Is Essential

    Calvus use their flattened bodies to squeeze into narrow rock crevices, so a rockwork-heavy layout with plenty of hiding spots is essential. Without enough shelter, they can stay stressed and rarely show their natural behavior.

  2. 2Mind Their Territorial Side

    They're generally calm but do hold a sense of territory, so keeping them close to conspecifics or similarly shaped fish can lead to skirmishes. Give the tank some extra room and spread hiding spots across several areas.

  3. 3A Crustacean-Based Diet

    In the wild they're ambush predators that feed mainly on shrimp and other crustaceans. They'll accept prepared foods, but sinking, shrimp-based pellets help match their natural diet.

  4. 4Prefers Hard, Alkaline Water

    Being native to Lake Tanganyika, they prefer slightly alkaline, hard water. They're sensitive to sudden shifts in water chemistry, so match temperature and parameters carefully during water changes.

  5. 5Slow, Steady Growth

    Adults reach about 13 to 14 cm, but they grow at a fairly unhurried pace. Give them time, and their true shape and coloring will come through gradually.

  6. 6Choose Tankmates Carefully

    Since they're calm, ambush-style feeders, other Lake Tanganyika cichlids with a similarly even temperament make good tankmates. Fast, aggressive feeders can easily out-compete them at mealtime.

  7. 7Acclimate Slowly at Introduction

    They're sensitive to water changes, so take time with drip acclimation when bringing one home. It's common for them to hide right after introduction, so give them space to settle in quietly.

Frequently asked questions about Calvus

Q.Is Altolamprologus calvus suitable for beginners?
A.It's considered a species better suited to intermediate keepers. Setting up a proper rockwork layout and maintaining stable water quality takes some care, so it helps to have prior tropical fish keeping experience first.
Q.Can it be kept with other fish?
A.It's calm by nature but does hold a sense of territory, so care is needed when pairing it with conspecifics or similarly shaped fish. Give the tank plenty of space and hiding spots, and monitor how tankmates get along.
Q.What should I feed it?
A.In the wild it feeds mainly on shrimp and other crustaceans. It will adapt to prepared foods, but adding sinking, shrimp-based feed helps match its natural diet.
Q.How large does it grow?
A.Adults reach around 13 to 14 cm. Growth is fairly slow, so it takes time to develop its full adult shape.
Q.What water conditions does it need?
A.Being native to Lake Tanganyika, it prefers slightly alkaline, hard water. It's sensitive to sudden changes, so water changes should be done gradually and carefully.

Useful tools for Calvus care

💧Aquarium Volume CalculatorCalculate water volume, weight, and heater wattage from tank dimensions🧪Water Quality CheckerFind compatible fish, shrimp, plants & corals based on pH, temperature & hardness🍽️Feeding GuideCheck feeding frequency, portion sizes & supplements by species and growth stage🤝Compatibility CheckerCheck compatibility between two species on a 5-level scale📊Fish Compatibility MatrixCheck fish compatibility at a glance with our matrix chart🔄Nitrogen Cycle GuideAuto-calculate bacteria colonization timeline for new tank cycling🗓️Seasonal Care CalendarMonthly care events and seasonal management tips at a glance🚿Water Change CalculatorAuto-calculate optimal water change frequency and volume by tank size and fish count🐠Stocking CalculatorCalculate max fish capacity for your tank size with overstocking alertsElectricity Cost SimulatorCalculate monthly and annual electricity costs for care equipment with presets🧬Breeding PlannerSelect parent varieties to view breeding schedules and offspring patterns🏞️Tank Layout PlannerGet substrate, plant & hardscape suggestions based on tank size and style🧮Care Cost SimulatorEstimate initial, monthly & annual costs by category, care level and quantity⚖️Species Comparison ToolCompare two species side by side: care difficulty, size, lifespan & temperature🎯Pet Match DiagnosticAnswer 7 questions to find your top 3 perfect pets📋Lifetime Cost SimulatorEstimate lifespan and lifetime costs by species for dogs, cats, reptiles and more🚚Transport Safety CheckerCheck transport safety score and precautions by category, season, method and distance💊Medication Dosage CalculatorCalculate proper medication dosage by body weight and medicine type for fish, reptiles, and small animals⏱️Quarantine & Acclimation TimerManage quarantine periods and acclimation steps with countdown timers. Includes recommended durations by species

Learn more about Calvus in the encyclopedia

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Care difficulty, lifespan, size and diet — all basics covered.

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