The balloonfish, also known as the spiny porcupinefish and spiny puffer, ranges worldwide in tropical waters and some subtropical and temperate areas. It is a member of the family Diodontidae, the spiny puffers. This fish, along with its close relatives, has the ability to inflate its body by taking water or air into portions of its digestive tract, increasing its diameter size by as much as three times. When the body expands, long spines that normally lie flat on the body are erected, not only adding to the apparent size, but also creating a formidable weaponry to discourage attack by most would-be predators.
These are usually large 5-9 inches. I generally have several in stock so if you have a size prefferance please request it in the note section at checkout.