What You Should Know Before Getting a Porcupine Puffer

Learn How to Care for Your Porcupine Puffer Fish Before You Bring Him Home

Porcupine puffers are engaging and intelligent saltwater fish that appear—and act—a bit cartoonish. They usually learn to interact with their human caregivers in odd and appealing ways; some even respond to eye contact by swimming up and begging for food! Their engaging personalities, combined with their big eyes, chubby cheeks, and silly grins, make them adorable pets.

Sometimes called balloonfish or porcupinefish, these fish are slow-moving and easy for divers to catch, making them readily available for purchase and relatively inexpensive compared to most other saltwater fish.

Sturdy Saltwater Pets

While they get rather large and require a big aquarium, their care is easy compared to that of many saltwater fish. They can handle fluctuations in pH, temperature, and salinity better than many other fish and don't go on hunger strikes as often in response to stress. These fish are actually rather sturdy creatures as far as saltwater fish go, so long as you give them proper care. If you maintain a healthy aquarium and feed your pet properly, you can enjoy his antics for many years.

All of these qualities make them very popular in the aquarium trade. This page will give you the basics on how to care for a porcupine puffer. Please research any species of fish you plan to keep as a pet before you buy.

What Is the Minimum Tank Size for a Porcupine Puffer?

The first thing to do before you buy a porcupine puffer is to make sure you have a big enough system to handle his size. To stay happy and healthy, his tank should be no smaller than 100 gallons, both so he has room to swim and to allow for enough biological filtration and water volume to handle his waste.

Why Are 100 Gallons Necessary?

As with all fish, you should always consider the adult size of the porcupinefish when deciding to put one in your marine aquarium. They are big and hefty fish that can reach an adult size well over a foot long. They are also often sloppy eaters who make a lot of waste. When it comes to aquarium fish, porcupine puffers are like SUVs when it comes to fuel efficiency. They go through a lot of fuel, and they create a bunch of pollution.

With Saltwater Tanks, Bigger Is Better—and Easier

It is also much, much easier to keep a large saltwater fish tank than it is to keep a small saltwater fish tank. The added volume creates greater stability, so small changes don't cause big problems nearly as quickly as they do in a smaller aquarium. Bigger is better, and extra gallons buy you time to tweak and make corrections before your fish suffer from them.

Don't bring your new pet home until you have a big, cycled saltwater aquarium to put him into.

How Do You Keep the Tank Clean Even Though They're Messy Eaters?

These fish require some extra work to keep things clean.

Water Changes

Because porcupine puffers create so much waste, be prepared to do a lot of water changes to remove this waste, even if you have a plenum or other nitrate-removing device in your aquarium. I'd recommend changing no less than 20% of the tank's water weekly to keep up with his waste production.

Vacuuming (and Reducing) Waste

You can also keep the water cleaner by removing any uneaten food and any visible waste using a tank vacuum to suck it out. If you feed frozen food, be sure to thaw the food thoroughly and discard any water it may have been packed in. The meltwater usually contains food juices that will spoil quickly in your display tank. Some aquarists also claim that feeding dry food can create more waste problems as it is not as completely broken down by your fish's digestive tract as fresh or frozen foods are.

This is part of the reason it's a good idea to house your puffer in the largest tank you can manage. A larger water volume dilutes wastes better than a smaller water volume.

Refugiums With Macroalgae

I've found the use of a refugium filled with chaetomorpha macroalgae kept on a twenty-four-hour light cycle helps a great deal with maintaining high water quality. My Porky's tankmates also enjoy eating the macroalgae that I harvest when it outgrows the hang-on-tank refugium.

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Trace Elements Are Important to Porcupine Puffer Care

Porcupine puffers are prone to developing deficiencies or thyroid issues if they don't get proper levels of trace elements found in seawater. This is yet another reason frequent water changes are important to their health. Frequent water changes help keep the levels of trace elements that are consumed by fish, plants, and invertebrates at the necessary levels.

If you also keep corals or rely on macroalgae filtration to minimize the frequency of water changes, it may be a good idea to supplement your tank with iodine per the instructions on whatever iodine supplement you purchase. Maintaining proper levels of iodine is important for thyroid health in pufferfish.

Supplemental Iodine for Thyroid Health

When added as directed, iodine supplements can help keep your puffer's thyroid healthy. Iodine supplementation is also important to the health of corals and other fish you may keep with them as the iodine in saltwater is usually used up in saltwater more quickly than other trace elements. While water changes can offset some of it, they can't offset enough unless they are done even more frequently than once a week. Iodine supplementation will allow you to strike a better balance, keeping water quality high and trace elements at healthy levels without wasting salt mix or effort.

I like the Kent Marine iodine supplement both because it already comes in a diluted solution which allows for greater accuracy in dosing compared to concentrates like Lugol's solution and because I've had excellent results with it. Pretty much all of their marine and reef aquarium supplements are foolproof and easy to dose.

Don't Forget They're Predators and Will Eat Invertebrates

Although their temperament is usually mild in regard to other fish, porcupine puffers are carnivores. Snails, crabs and hermit crabs, clams, barnacles, and shrimp of all kinds are all part of their natural diet.

Never forget their predatory nature because some saltwater aquarium inhabitants might be seen as food rather than tank mates. Even that fancy cleaner shrimp may look like a snack to your pufferfish. Mobile invertebrates are almost all on his menu of favorite foods. Corals, however, are a very individualized matter. Some individuals will eat or bite some or all types of coral, while others will leave coral alone. Soft fleshy polyps of any sort are particularly tempting, even if not edible, and most balloonfish will take a little taste.

What Do Porcupine Puffers Eat?

Porcupine puffers' teeth continue to grow their entire lives. Their teeth, sometimes referred to as beaks, must be ground down by the consumption of hard-shelled foods. They both love and need crunchy invertebrates to eat.

If your pet's teeth become overgrown, he may become unable to eat and starve to death or require delicate dental surgery few veterinarians are willing or able to perform. If you want to keep your puffer's teeth ground down, be sure to feed him plenty of shell-on seafood, preferably at least a few times a week. While many porkies will crunch on ground coral just for fun, you can't count on all of them to do it enough to keep their teeth trimmed.

Warning: Do Not Feed Them Fish

Balloonfish are not piscivores. That means that, in nature, they don't eat fish. Do not feed fish, live or dead, to them. Feeding fish to pork puffers may cause something called fatty liver disease, a usually fatal ailment. Not only that, but the nutrient balance found in fish is very different from that found in mollusks and crustaceans, their natural prey. Feeding fish, especially live feeder fish, to your porcupine puffer can also unnaturally accustom him to eating fish, making him a danger to future tank mates.

What About Prepared Fish Foods?

Carefully read the ingredients of any prepared fish foods you give your pet. Choose those with invertebrates, such as shrimp, krill, squid, clams, or mussels, listed as their first ingredient. Avoid all prepared fish foods with any type of grain or fish meal listed first in the ingredients.

Can I Feed My Puffer Frozen Seafood?

If you buy frozen seafood for your Porky read the packaging to make sure it has no added preservatives or ingredients. Fish are much more sensitive to odd chemicals than people are. If you buy mussels or clams from the seafood counter, be sure they are closed up tight which indicates they are alive. I prefer to let them sit in a bucket of used saltwater from a water change overnight to make sure they are alive and healthy before giving them to Porky.

Watch a Puffed Up Porcupine Puffer Deflate

This pufferfish parent was quick with his video camera and caught his young porky deflating. I think it's adorable! The little damselfish popping into view is pretty cute, too.

Natural Defense Mechanisms: Will My Balloonfish Puff Up?

Porcupine puffers have a dual natural defense mechanism. They are called puffers or balloonfish for a very good reason—they fill their bodies with water when frightened. This causes their bodies to look huge and their spines to stick out. Many a predator would change his mind when faced with a weird spiky ball instead of the fish he saw a moment ago or spit out a little morsel that suddenly sprouted sharp spines.

The fish in the picture, Porky, is only partly puffed. It is very hard to photograph him in a puffed-up state as he comes swimming over, begging for food as soon as he sees me, deflating along the way.

Don't try to scare your pet into puffing; it's very stressful for them when they puff in a panic. Given time, you'll eventually see him blown up like a balloon, an occurrence more frequent in very young specimens. It is thought that they occasionally puff to keep their skin flexible and to clean off built-up debris that gets on their spikes which usually lay flat and mostly inside their skin.

Their other defense mechanism is having poisonous flesh. Porcupine puffers have a deadly toxin in their internal organs called tetrodotoxin. This makes it unlikely that a fish that eats one will ever eat another, as dead things don't eat. Each moderate-sized balloonfish contains enough toxin to kill several human beings.

Oddly enough, the neurotoxin found in their flesh is exactly what entices foolhardy gourmands to eat fugu or sashimi made from pufferfish. In very tiny quantities, the toxin causes tingling and euphoria—and sometimes death.

So, whatever you do, don't eat your pet puffer!