Yellow boxfish

Care at a glance

The yellow boxfish is, as a juvenile, a bright yellow cube with black spots, which makes it one of the most endearing reef fish; adults grow larger, more elongated and bluish grey. Its body sits in a rigid bony armour, so it can only steer with its fins and therefore moves slowly and hoveringly.

Under severe stress it can release a toxin that in a closed aquarium can kill every fish, including itself. That makes it no beginner's species: keep it alone, calmly and without fin nippers, and be extremely careful when catching and transporting it.

Good to know

• Outgrows most home tanks
• Palytoxin risk — wear gloves
• Preys on shrimp and snails

Related species

• Dogface pufferArothron nigropunctatus
• Volitans lionfishPterois volitans
• Lined seahorseHippocampus erectus
• Porcupine pufferDiodon holocanthus
• Bluethroat triggerfishXanthichthys auromarginatus
• Dwarf seahorseHippocampus zosterae