15 Perplexing Puffer Fish Facts

Here's a collection of fascinating facts about the fugu fish, also known as the puffer fish.

If you crossed a hedgehog with a fish, you’d get a puffer fish. This majestic, inflatable sea beast is one of the most unusual aquatic animals ever, with a unique set of defense mechanisms that put electric eels to shame.

Keep reading for 15 things we never would have guessed about Mrs. Puff.

There Are More Than 70 Types of Saltwater Puffer Fish

Spot-fin porcupinefish ( Diodon hystrix ) famliy balloonfish on Red Sea - Marsa Alam - Egypt

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First off, there isn’t just one kind of puffer fish. There are more than 120 different puffer fish species, and the majority of them are marine-water fish.

So, if you brought one home from a tide pool at the beach and dumped them into a freshwater aquarium, it wouldn’t last long.

Plus Over Two Dozen Freshwater Puffers

Spotted green pufferfish on black background

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In addition to the plethora of saltwater puffers, there are 29 species of freshwater puffer fish.

An additional 40 live in brackish water, which is a mix of salt and fresh water.

They Come in All Sizes

Green pufferfish or speckled pufferfish (Dichotomyctere nigroviridis) in an aquarium with marine vegetation

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Puffer fish are surprisingly diverse in size. They can be as tiny as the 1-inch-long pygmy puffer or as huge as the freshwater giant puffer, which can reach more than 2 feet in length.

Imagine running into an angry beach ball while going for a swim.

All Puffers, However, Share a Unique Defense Mechanism

Fish hedgehog. Yellow-spotted cyclicht - grows up to 34 cm, feeds on crustaceans and molluscs. In case of danger, it takes the form of a ball, bristling spines.

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Regardless of what type of water they dwell in, all puffer fish share the defense mechanism they’re known best for: the ability to puff up with air or water to more than double their usual size. They do this in response to threats in hopes of looking larger and more intimidating to potential predators.

Imagine you’re a shark. Now, look at the puffer pictured and tell us you wouldn’t think twice about trying to eat it. Hard pass.

Mrs. Puff May Be a Boating Teacher, but She’s Not the Fastest Swimmer

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We don’t mean to be rude, but one glance at a puffer fish is enough to tell you that they’re not the most athletically inclined of creatures. Their tail acts as a rudder while their small fins help propel them forward, but they’re painfully slow-moving. They’re not terribly good at changing directions, either.

Luckily, they have excellent vision, which makes it easier to spot danger quickly and make an escape. They can swim quickly for a short period of time, and they always have their puffing mechanism as a last resort.

Despite Their Goofy Appearance, Puffer Fish Are Tough

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If a puffer fish is caught by a predator, taking them down won’t be a fun experience. These scrappy sea balloons have either sharp beaks, teeth or both that they can use against their enemies.

If a hungry dolphin does try to gobble them, swallowing a puffed-up puffer covered in sharp spines is no walk in the park. Basically, if you’re trying to take a puffer fish down, you’re going down with them. Many aquatic animals try to prey on puffers, but only a handful are immune to their toxins. These include sharks and a few species of sea snakes.

Puffers Don’t Have Any Scales

Blackspotted puffer - Arothron nigropunctatus or dog-faced puffer. Tropical marine fish belonging to the family Tetraodontidae.

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Not every fish has scales. Shocking, right? Puffer fish have smooth skin covered in spines. The spines lay flat until they puff up, so they’re not easy to see most of the time.

Their smooth skin, however, makes them extremely sensitive to water quality. Any pollutants or rapid changes in temperature can take out a puffer fish quickly.

They Can Technically Be Kept as Pets

Tetraodon Fahaka fish swims in aquarium on green background (Tetraodontidae)

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For the reason mentioned earlier, puffer fish aren’t recommended for beginner fish keepers. They’re popular in the aquarium trade, but because they demand such specific water parameters, it’s wise to wait to purchase them until you have experience keeping some hardier fish.

Once you master the art of monitoring water quality, measuring nitrite, nitrate and ammonia levels, along with water hardness and pH, you’re probably ready to stock your aquarium with puffers.

If You Do Purchase a Puffer, Don’t Keep It With Other Fish

Close-up of porcupine puffer fish in aquarium with blurred colorful background

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Expanding on that whole “not for beginners” thing, puffer fish require plenty of space. A 20- to 30-gallon aquarium will suffice for smaller species, but some species require 100-gallon tanks or larger for optimal health.

They also can’t be kept in a community tank with other fish species because puffers are notorious for snacking on their tank mates. If other fish are too big to eat, they’ll nip at their fins and stress them out. It’s not the puffer’s fault. They’re just weird, bubble-shaped carnivores.

Puffer Fish Have an Odd Diet

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While we’re talking about puffer fish food habits, they eat an extraordinarily wide variety of foods in the wild. They need a diet high in minerals to stay healthy and keep their spines in tip-top shape, so they dine on numerous shellfish, crustaceans, snails and fish.

They’ll eat virtually anything they’re offered in captivity, but it’s important to offer them a varied diet to keep them feeling their best and prevent illness. Things like brine shrimp, bloodworms and scallops are ideal, but stick to frozen food to avoid exposing puffer fish to potential parasites.

Puffer Fish Teeth Grow for Life

Arothron nigropunctatus yellow. fugy fish

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Puffer fish, unlike most fish species, have teeth that never stop growing. That’s because they spend so much time eating extremely hard foods.

If they don’t wear down their teeth by gnawing on shells, their teeth may grow too long and prevent them from eating at all. In the wild, this leads to starvation. In captivity, it leads to an expensive trip to the vet.

They’re Adorably Romantic

couple of puffers swim in beautiful tropical coral reef in Surin Island, Phang nga, Thailand

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Puffer fish aren’t the most welcoming to strangers, but they’re quite affectionate with each other. As part of the puffer fish reproductive cycle, male puffer fish help support their mates while they’re laying their eggs by swimming alongside them in the water and gently rubbing against their sides.

Puffers Live About 10 Years

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When puffer fish are raised in captivity in ideal conditions, they typically live for about a decade. In the wild, they’re likely to get gobbled up a bit sooner. Fortunately, their spines make them less likely to become lunch than most other fish species.

That’s a plus since they take a while to reach adulthood and usually aren’t ready to reproduce until around the age of 5. When they do, they lay between three and seven eggs, which take about a week to hatch.

They’re Very, Very Tasty

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A puffer fish isn’t the easiest fish to catch and prepare, but in Korea, China and Japan, they’re considered a delicacy.

Known as fugu fish, their meat has a subtle, clean flavor with a unique texture that many seafood fans adore.

Improperly Prepared Puffer Fish, However, Can Kill You

Puffed up blowfish swimming underwater in the ocean

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As scrumptious as they are, never try to prepare fugu fish on your own. Their spines contain a toxin called tetrodotoxin. The toxins can actually be found throughout the fish’s body, and if prepared improperly, they can cause lethal paralysis.

Most of the time, eating fugu fish is fine, but a few diners perish every year from consuming incorrectly prepared puffer fish. Munch them up at your own risk!

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