TankBud

Porcupine puffer

Diodon holocanthus

Also known as Balloonfish, Long-Spine Porcupinefish, Freckled Porcupinefish

SaltwaterFish

Porcupine puffer (Diodon holocanthus)
Diego Delso · CC BY-SA 4.0

Care at a glance

Temperature
75–81°F
24–27°C
pH
8.1–8.4
Adult size
11.8 in
30 cm
Minimum tank
180 gal
680 L
Temperament
Mostly peaceful
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Diet
Carnivore
Difficulty
Medium
Breeding
Hard
Rarity
Common
Reef safe
Not reef safe
Family
Diodontidae
Origin
Circumtropical reefs across the Atlantic, Indian, and Pacific oceans

Overview

The porcupine puffer is one of the more personable large puffers. It often recognizes its keeper and begs at the glass at feeding time. It suits a fish-only or FOWLR tank and a keeper with a little experience.

Did you know

When the porcupine puffer inflates, folded skin and an oversized, non-digestive stretch of stomach unfurl to hold the extra water. The stiff, elastic skin around that water-filled core forces the spines, normally flat, to snap upright. They stay up until the fish deflates again.

Caring for the porcupine puffer

Give the porcupine puffer a tank of at least 180 gal (680 L). It is a heavy waste producer and needs strong filtration on top of the swimming space. Give it a few real hiding spots as well as open room to patrol after dark.

Keep the water at 75 to 81°F (24 to 27°C) with a pH of 8.1 to 8.4. Avoid netting it if you can. Startled or handled roughly, it will inflate and can gulp air that is difficult to release afterward.

Its beak grows continuously, so feed hard-shelled foods such as snails, clams and shell-on crab or shrimp regularly, alongside squid and other meaty fare. That hard food is what wears the beak down.

The porcupine puffer is mostly peaceful with fish too large to swallow. It will eat snails, hermit crabs, shrimp and other invertebrates on sight, so it is not reef safe. Breeding it is hard.

Good to know

The porcupine puffer belongs to the porcupinefish family Diodontidae. The family is named for its beak, formed from just two fused tooth plates, one per jaw. True puffers in Tetraodontidae have a four-plate beak instead. Inflating is a defense that can double or triple its size in seconds. Unlike Arothron and Canthigaster puffers, it carries only trace amounts of tetrodotoxin, mostly in the ovaries. That makes it considerably less toxic than its Tetraodontidae relatives, though its flesh is still not safe to eat.

In the wild

The porcupine puffer is one of the few reef fish found nearly worldwide in warm water. It turns up on grass flats, coral reefs and around mangroves across the Atlantic, Indian and Pacific oceans. It lives at depths of about 2 to 35 m. It spends the day tucked into a cave or ledge and comes out at night to forage over sand and rubble.

Common questions

What size tank does a porcupine puffer need?

A porcupine puffer needs at least 180 gal (680 L). It spends most of its time in the bottom.

What temperature and pH does a porcupine puffer need?

A porcupine puffer is comfortable at 75–81°F (24–27°C) with a pH of 8.1–8.4.

What does a porcupine puffer eat?

A porcupine puffer eats squid and other meaty fare, plus hard-shelled foods such as snails, clams and shell-on crab or shrimp. The hard food wears down its ever-growing beak.

How big does a porcupine puffer get?

An adult porcupine puffer reaches about 11.8 in (30 cm).

Related species