Horn shark (Heterodontus francisci) care guide

Group
Marine fish
Family
Heterodontidae (bullhead sharks)
Water
saltwater
Maximum size
122 cm
Temperature
20–24°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Care level
expert
Temperament
semi_aggressive
Reef safe
no

Care

Tank and decor: at 122 cm adult length this shark outgrows home aquaria and is for public-aquarium-sized systems. The list quotes a minimum of 240 US gallons (about 910 litres), with a large footprint of open sand and smooth rockwork. Strong filtration and a secure cover are essential. Water: the list describes it as a subtropical species. Our sources give no further figures, so the values here are general marine aquarium guidance, not species-specific: 20–24 °C, pH 8.1–8.4 and specific gravity 1.023–1.026. A chiller is usually needed. Sharks are sensitive to copper and many other medications. Behaviour and identification: a stout, slow bottom-dweller with a ridge over each eye and a spine in front of each dorsal fin. The list says it is the most common bullhead shark in the North American trade. At up to 122 cm it is for public-aquarium-sized systems. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies). Checked October 2026.

Diet

Carnivorous. Feed a varied diet of meaty marine foods such as squid, prawn, mussels, clams and fish pieces, with a vitamin and iodine supplement to help prevent goitre. Feed two or three times a week to appetite rather than daily; overfeeding causes fast growth and health problems.

Breeding

Our sources for this page give no species-specific breeding details.

Compatibility and tank mates

Not reef safe: it digs in the sand, knocks over unsecured rock and eats crabs, shrimps, snails and small fish. Keep it with large, peaceful fish that will not nip it, and avoid triggerfish, large angelfish and puffers, which may bite fins and skin. Its strong jaws crush shellfish, so no invertebrates are safe.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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  • Live fish and other vertebrates must be sent by specialist live-animal couriers (for example APC Overnight or DX Express), never by Royal Mail. Some invertebrates and plants may go by Royal Mail Special Delivery or 1st Class within its rules.
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