Spotfin porcupinefish (Diodon hystrix) care guide

Group
Marine fish
Other names
Spot-fin porcupinefish, Spotted porcupinefish, Black-spotted porcupinefish, Porcupinefish
Family
Diodontidae (porcupinefishes)
Origin
Tropical and subtropical seas worldwide, including the Mediterranean; lagoons and reefs at 1–50 m, sheltering under ledges and in caves by day.
Water
saltwater
Maximum size
91 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.020–1.025
Care level
expert
Temperament
peaceful
Reef safe
no

Care

This porcupinefish can reach 91 cm (about 40 cm is more typical for adults), so it outgrows home aquaria and is for public-aquarium-sized systems only. Water figures given here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and a specific gravity of 1.020–1.025 (fish-only systems can run at the lower end). Puffers produce a lot of waste, so strong skimming and regular water changes matter. It is solitary except when breeding and mostly active at night, especially around dusk and dawn. When threatened it swallows water to inflate and raise its spines. It is white or pale with many small black spots, including on the fins. Juveniles live in open water until about 20 cm long. Toxins: it concentrates tetrodotoxin in its liver, skin, gonads and gut and must never be eaten. 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); Wikipedia (en.wikipedia.org/wiki/Diodonhystrix). Checked October 2026.

Diet

Feeds on sea urchins, sea snails and crustaceans, which it crushes with its beak. In captivity it needs whole shellfish, crab and other hard-shelled foods.

Breeding

The sources give no breeding details beyond the fish pairing up only to mate. Not bred in home aquaria.

Compatibility and tank mates

Not reef safe: it eats urchins, snails and crustaceans. Suits only very large public-aquarium displays with robust tankmates.

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

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