Spotted Sharpnose Puffer

The spotted sharpnose puffer is one of the most commonly sold small sharp-nosed pufferfish (Canthigaster, "toby"). Its body, which varies between orange and reddish brown, is covered with light blue spots; there are wavy blue lines on the back and around the eye, and a dark eyespot at the base of the dorsal fin. The color pattern varies by region. Its Indian Ocean look-alike C. petersii and its Red Sea look-alike C. margaritata are separate species and may be sold under the same name in the trade.

Toxin note: The skin and internal organs of pufferfish contain a powerful toxin called tetrodotoxin. It poses no danger to the fish in the aquarium, but these fish must never be eaten. Specimens are wild-collected.

It lives on sheltered rocky reefs, tidal flats, lagoons and outer reefs, often among corals or under overhangs. It is seen in pairs or small groups. In the wild it feeds mainly on filamentous and calcareous red and green algae, as well as corals, tunicates, mollusks, echinoderms, worms and crustaceans.

• Volume: At least 150 liters and 90 cm in length; plenty of hiding places.
• Water: Salinity specific gravity 1.023–1.026, pH 8.1–8.4, temperature 24–27°C.
• Decor: Rock crevices to sleep in at night and shelter in when in danger.
• Reef compatibility: Reef-safe with caution, but on the risky side. It eats small shrimp, hermit crabs, snails and tube worms; some specimens pick at LPS and soft corals and at the mantle of Tridacna clams.

Omnivorous. Offer frozen mysis, chopped mussels and shrimp, small shelled snails, krill, dried seaweed and marine fish granules. Shelled foods (mussels, small snails) should be offered a few times a week to wear down its constantly growing teeth. It should be fed twice a day.

A curious, active fish that recognizes its keeper. It may nip the fins of slow-swimming or long-finned fish. When in danger it can inflate by swallowing water; this is a sign of severe stress, so never make the fish inflate by taking it out of the water.

Good companions: Tangs, damselfish, larger clownfish, wrasses, dwarf angelfish, foxface, fish that are faster than it and short-finned.

Avoid: Seahorses, pipefish, mandarin fish, slow long-finned fish, ornamental shrimp, snails and hermit crabs.

Kept as a single specimen in the aquarium. In the wild it can form pairs, but in the aquarium two individuals often fight.

In the wild the female lays her sticky eggs in clumps of algae on the bottom. Breeding in the home aquarium is rare and fry are not raised.

• Tooth overgrowth: If shelled foods are not offered, the teeth grow too long and the fish becomes unable to eat.
• Marine white spot: Because of its scaleless skin it is prone to the disease.
• Copper sensitivity: Pufferfish are sensitive to copper treatment; a low dose and close monitoring are needed.

Cannot be reliably distinguished externally.