Horn Shark

Also known as California Horn Shark

The Horn Shark is a fascinating and hardy species native to the Pacific coast of North America, featuring a mottled brown pattern and distinctive horn-like ridges above the eyes. This docile, slow-moving bottom-dweller is one of the most cold-water tolerant shark species and an excellent choice for experienced aquarists with cooler water systems. Known for its peaceful temperament and unique appearance, this species is manageable and relatively easy to care for compared to many sharks.

Key Features

• Scientific Name: Heterodontus francisci
• Common Names: California Horn Shark, Horn Shark
• Adult Size: Up to 36–48 inches
• Lifespan: 15-25+ years with proper care
• Temperament: Extremely docile; non-aggressive
• Reef Compatibility: Not reef safe; predatory
• Minimum Tank Size: 500 gallons preferred
• Experience Level: Advanced; requires cooler water system

Habitat & Tank Requirements

Tank Environment: Requires large tank with extensive sand bed for resting. Provide caves, rocky ledges, and hiding spots with smooth surfaces. Strong filtration with calm resting areas near bottom. No sharp decorations or rough surfaces. Subdued lighting preferred.

Water Parameters:

• Temperature: 55-68°F (13-20°C) – cold water species
• Salinity: 1.023-1.026
• pH: 8.0-8.4
• Excellent water quality essential

Equipment Recommendations:

• High-capacity filtration system
• Large protein skimmer
• Strong water circulation
• Chiller REQUIRED (cold water species)
• Sand substrate
• Subdued lighting

Chillers are absolutely mandatory for this cold-water species.

Diet & Feeding

Horn Sharks are carnivores specializing in hard-shelled invertebrates.

Recommended foods include:

• Primary: Hard-shelled prey (crabs, large shrimp with shells, snails)
• Variety: Whole fish (silversides, smelt), squid, mussels, clams, sea urchins
• Natural diet: Sea urchins are favored food in wild
• Supplements: Vitamin-enriched foods weekly

Feeding Frequency: 3-4 times weekly; large meals

Special Note: Powerful crushing jaws designed for hard prey. MUST have regular access to hard-shelled foods to wear down continuously growing teeth. Primarily nocturnal feeder.

Social Structure & Compatibility

• Tankmates: Compatible with other cold-water fish too large to eat
• Extremely Peaceful: One of the most docile shark species
• Multiple Sharks: Can coexist with other peaceful sharks in large systems
• Predatory: Will consume small fish and invertebrates

Notes & Considerations

• One of the most docile and handleable shark species.
• Mottled brown camouflage pattern helps blend with rocky substrate.
• Distinctive horn-like ridges above eyes give species its name.
• Spines present on both dorsal fins (handle with care).
• Native to Pacific coast from California to Mexico.
• REQUIRES COLD WATER: Cannot survive in tropical temperatures.
• Chillers are absolutely mandatory; this is non-negotiable.
• Thrives in 55-68°F range; warmer temperatures cause stress and death.
• Excellent choice for cold-water or temperate marine systems.
• Extremely slow-moving; sedentary bottom-dweller.
• Primarily nocturnal; hides during bright daylight hours.
• Harmless to humans; very docile and can be carefully handled.
• Powerful jaws can crush sea urchin shells and thick-shelled prey.
• Teeth grow continuously; hard-shelled diet essential for dental health.
• Will eat any fish small enough to swallow.
• Not compatible with small fish or ornamental invertebrates.
• Very sensitive to copper medications; never use copper treatments.
• Skin lacks scales; avoid rough surfaces to prevent abrasions.
• Produces substantial waste; excellent filtration required.
• Oviparous (egg-laying); produces distinctive spiral egg cases.
• Females lay unique corkscrew-shaped egg cases (mermaid’s purses).
• May breed in aquariums if male and female are housed together.
• Males easily identified by prominent claspers.
• Very long-lived; 20-25+ years not uncommon.
• Hardy and disease-resistant in proper conditions.
• One of the easiest sharks to maintain if temperature requirements met.
• Legal to collect in some areas with proper permits.
• Check local regulations before acquisition.
• Represents long-term commitment of 20+ years.

Why Choose a Quarantined Horn Shark?

Purchasing a quarantined specimen from us means you’re starting with a healthier, properly acclimated shark. All specimens are carefully observed, treated appropriately (never with copper), and trained to accept varied hard-shelled foods before sale. Given the specific cold-water requirements, professional quarantine ensures proper temperature acclimation and provides the strongest foundation for long-term success with this fascinating species.