Porcupine Fish

Introduction

I’ve had lot of people ask me about the Porcupine Fish I keep in my reef aquarium. I decided to put together this post to answer questions related to keeping a Porcupine Fish as well as Marine Puffers and even Freshwater Puffers. The content in this post is based on my personal experience keeping these fish. I welcome feedback and others experiences. Porcupine Fish, often listed as Porcupine Pufferfish, are technically not Pufferfish. The two are used interchangeably within the aquarium hobby though. Porcupine Fish belongs to the Diodontidae family while the Pufferfish belongs to the Tetraodontidae family. Both animals have other individual differences and peculiarities, but their similarities, compared to other marine aquarium fish, far outweigh their differences. There are also brackish and freshwater Puffers suitable for the home aquarium with different tank, water and feeding requirements. For the purpose of keeping Porcupine Fish and Marine Puffers in the home aquarium, I am going to refer to them both as just Puffers and treat them the same. I’ve been keeping Puffers since I first got into the hobby and have learned many things that have allowed me to keep these guys successfully for many years. In fact, I’ve always kept at least one Puffer in one of my aquariums since the early 90s. I currently have two. I have a Porcupine Fish in a 220 predator reef tank and a Freshwater Abei Puffer in a 50 gallon planted tank.

Water Parameters

Puffers do just fine in typical water parameters found in FOWLR to Reef Tanks. Due to their feeding requirements, they produce a lot of waste so adequate filtration is a must. I wouldn’t keep one without an oversized skimmer or a good algae filter. Puffers tend to be more sensitive to ammonia than most fish. In established tanks, it’s usually not an issue. But when adding one to a newer aquarium or quarantining them, it’s very important to keep ammonia undetectable. Regular water changes until the aquarium’s filter (bacteria population) is capable of processing the increased waste is the best way achieve this. If quarantining without biological filtration, Seachem Prime can be used. However, you will still need to do water changes to remove the bound ammonia. Tank Size Smaller Puffers can be kept in a 75 gallon for the first year or so but will require a larger tank very soon. I would not keep a 6″ Porcupine Fish in anything smaller than 180 and even that is pushing it. The two main issues with smaller tank size is that they grow large very quickly and need swimming room, and they eat a lot and as such produce a LOT of waste. It requires a lot of good filtration to break down their waste and keep nutrients from overwhelming the aquarium.

Water Flow

Puffers are not the most agile swimmers. They’re more like helicopters than airplanes. I like to keep flow strong enough to keep waste suspended in the water column to be filtered, but random so they don’t get blasted swimming in front of the pump or wave maker. I’ve actually had one get stuck to a wave maker because it got too close to the suction and the wave maker was on steady flow. Luckily I caught it in time.

Personality

Probably the main reason Puffers are so popular is that they have great personalities. They are often referred to as the fish version of a dog. They can recognize and spot their owner from across the room and swim right to the front glass shaking with excitement. They will often spit water out of the aquarium at or to get the owners attention. I’m sure this is mostly food motivated but fun never the less. Most importantly, they have that Bulldog cuteness to them and always seem to be smiling. They even don’t mind being petted but be careful as they will absolutely bite your finger if it gets close to their mouth. Puffers do sleep and on more than one occasion I thought my guy was sick as he was just laying lifeless on the sand bed or rock work not reacting to other fish swimming right next to him. It turns out that he was just sleeping. I’ve seen this countless times now and am able to recognize this behavior now.

Tank Mates

None of my Puffers have been particularly aggressive toward other fish. They can, and many times will, eat anything small and slow enough to fit in their mouth. I would avoid sand and rock dwelling gobies and blennies. Also most invertebrates will become a snack sooner than later. That means no clean up crew. While I’ve never had it happen to me, I always advise to stay away from poisonous spined fish like Lion Fish or Scorpion fish. Due to their bumbling swimming patterns, they could easily swim right into one of them by accident.

Feeding

Puffers pretty much eat anything they can catch. Most of the time that would be invertebrates, usually crustaceans and mollusks. But being the opportunist that they are, if they can catch a fish, they will. While many people like to feed live food, it’s not the best option as it can be messy, bring in parasites and be expensive. Plus it will encourage them to go after the live inhabitants in the aquarium that are not meant to be food. I feed primarily clam, shrimp, squid, octopus and occasionally a piece of fish. All of which can be bought at the local grocer or fish market for a fraction of the price of LFS frozen foods. I also feed Nori daily as they do ingest plenty of algae picking at rocks. They should NOT be fed Krill as their primary food as it will lead to a nutritional deficiency and cause lockjaw. Puffers are not able to see their food right in front of their face due to the wide set eyes. They usually spot it up to several inches away and then blindly burst into the food chomping away. It’s easy for them to be out competed for food by more aggressive feeders like Triggers, Large Wrasses, Tangs and Angels. Occasionally those fish pay the price if the Puffer gets to the piece of food at the same time. I’ve had half a Trigger’s face stuck in my Porcupine’s mouth for several seconds. And I currently have a Long Nose Hawk with a broken beak because he got too close. Puffers teeth continue to grow throughout their life. As Pufferfish develop into adulthood, their front teeth fuse together and jut forward, forming a tough, beak-like structure. Porcupine Fish have a strong upper and lower bite plate on each jaw. Both species use their teeth/plates to crack open the crustaceans and shellfish that form part of their diet. In this way they are able to grind them down so they don’t become overgrown. In the aquarium, it’s important to provide hard shelled food to keep their teeth from growing to large. When this happens, they are not able to open their mouth enough to eat. The fish will then need to be sedated and the teeth clipped or trimmed with a Dremel tool. I find feeding hard shelled foods extremely messy increasing the bio load of the aquarium. Not to mention the unsightliness of tons of broken shells all over the sand bed. I feed my Puffers with a pair of large stainless steel feeding tongs. I roughed up the outside tips with a file and I let them bite down on it at every feeding. I’ve been doing it this way for over 20 years and have never had overgrown teeth. Below is an example with my Freshwater Abei Puffer.

Health

Puffers can be prone to Ich, Flukes and internal parasites. I think it’s important to treat them in quarantine prior to adding them to an already stocked aquarium. Puffers are more sensitive to many meds than most fish so it’s important to keep a close eye on them when treating. If using a quarantine tank for treatment, monitor ammonia closely & perform water changes as necessary as they are very sensitive to that. At the very least, I would treat them with Praziquantel. This is well tolerated and can be done over a week in quarantine or in the aquarium. It will cover internal parasites as well as flukes and is not disruptive to the typical FOWLR aquarium. It’s also not uncommon for the eyes of Puffers to get damaged and subsequently infected. Erythromycin is the antibiotic of choice for eye infections. This should be done in quarantine if possible. Puffers will sometimes get Lymphocystis, Bacterial Tufts or Viral Nodules when water quality or nutrition is less than adequate. This will usually go away with improved water quality and a more varied diet with added vitamins. Humblefish & Reef is a great source for anything marine aquarium related but especially for fish disease and treatment.

https://humble.fish/community/index.php?threads/medications-and-treatments.4/

https://humble.fish/community/index.php?threads/bacterial-tufts-viral-nodules.6799/

Conclusion

Puffers make great pets as long as you have room for a large aquarium and provide the excessive filtration to meet their needs. They do well in reef aquariums with soft corals and many LPS corals that can tollerate higher nutrients. They may damage SPS corals and will certainly eat invertebrates so those are probably best avoided. With a proper diet and good water quality, you should be able to enjoy your Puffer for 10+ years.

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