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MBU Puffer Fish: Everything You Need To Know

MBU Puffer Fish: Everything You Need To Know

The MBU puffer is the largest freshwater species of pufferfish. It’s probably one of the largest species of freshwater aquarium fish readily available to hobby aquarists. As such, this fish is not for novice owners. It needs a lot of space and unique care needs. 

MBU is short for Mbuna, so they’re also commonly called MBU puffer fish. The size and unique skin of these fish means you need to create a highly specific tank environment for them to thrive. Many owners love them for their intelligence and interactive nature. 

If you’re interested in bringing one of these fish home, make sure you do a lot of research. These aren’t beginner-friendly fish, so you’ll need to arm yourself with the right knowledge. This article will get you started on your research journey. 

MBU Puffer Fish Species Overview & Natural Habitat

  • Common name: MBU puffer fish, Mbu puffer fish, giant puffer fish, giant freshwater puffer fish, giant puffer, Mbu puffer, African puffer fish
  • Scientific name: Tetraodon mbu
  • Care level: Difficult
  • Size: 22 – 30 inches  (55 – 75 cm) 
  • Life Span: Around 10 years
  • Temperament: Affectionate and interactive
  • Diet: Carnivore
  • Group Size: Best kept alone
  • Minimum tank size: 500 gallons at minimum, 1000 gallons is recommended
  • Tank level: Bottom-mid dweller
  • Water temperature: 75°F – 79°F (24°C – 26°C)
  • Water pH levels: 7.0 to 8.0
  • Water hardness: 10 to 25 KH

This Mbu puffer originates from the freshwater rivers and lakes in Congo, Cameroon, Tanzania, Burundi, and Zambia. Growing up to 30 inches in length, Mbu puffers are a challenging species to look after.

Appearance & Size

These fish are big, ranging from 22 inches (55 cm) to 30 inches (75 cm) in length.

With their deep olive green and yellow markings, the top of their body bears a striking resemblance to that of a leopard. But it’s not just their markings that make these fish stand out. The yellow shading extends underneath their belly, adding to their overall visual appeal. Their torpedo-shaped body, small semi-transparent fins, and gorgeous yellow tail complete the picture of a truly stunning fish.

These playful fish are sure to bring a smile to your face, with their whimsical smile and big eyes that grow further apart as they age. While their “teeth” may catch your attention, these are actually a beak that continues to grow over time. It’s essential that they receive a diet rich in crustaceans, or else the beak can become overgrown, making it impossible for the Mbu puffer to feed.

The Mbu puffer boasts a unique feature: instead of scales, its supple and stretchy skin allows it to “puff up” when startled.

Personality & Behavior

Mbu puffers are exceptionally intelligent and known for being affectionate and interactive with their owners. However, they’re aggressive towards other fish. For this reason, tank mates aren’t recommended, not even other Mbu puffers. They’re naturally solitary creatures, so living alone won’t affect their health.

Despite aggression towards other fish, their affectionate, playful nature towards humans is one of their most attractive features. Some aquarists have given them the nickname “water puppies” as a result of this behavior. Mbu puffers bond with their owners and will crave their attention.

You can interact with them through the glass by getting them to follow your finger. They’re also trainable to a certain extent. For example, you can train them to take food from your hand. If you decide to put your hands in their tank, exercise caution and wear protective gloves. 

Puffers have sharp beaks that can take off a finger. They also carry tetrodotoxins that can cause paralysis. Honestly, I would recommend keeping your bonding time through the glass. You can still enjoy a lot of interaction that way.


When kept in captivity, the average lifespan of the Mbu puffer fish is approximately ten years. Although they are believed to have a longer lifespan in the wild, living up to a decade is considered standard for those living in a confined habitat.

MBU Puffer Care & Tank Set Up

Besides the specific tank size and water parameters needed, you need to be careful with your decor. Pufferfish don’t have scales, so they’re more prone to injury than other fish. Avoid plastic plants with sharp edges or anything that has spikes. 

The safest decor items for a puffer include:

  • Soft substrate
  • Round rocks
  • Polished driftwood
  • Live plants

Exercise caution with live plants. Make sure any introduced plants have soft leaves to prevent injury. Puffers aren’t interested in eating plants, but they can have some rowdy play habits that may damage them. 

You should also keep decor to a minimum. Your puffer will want some decor for enrichment, but you need to give them extra space to ‘puff.’ Puffers can expand to three times their normal body size when they puff up. 

Mbu puffers are large to begin with, so err on the side of more space to account for this. Puffing up in a compressed space or onto sharp objects can damage their skin.

Aquarium Nitrogen Cycle

Mbu puffer fish are sensitive to poor living conditions and produce a lot of waste, so it’s important you cycle the tank regularly. The nitrogen cycle is one of the most important aspects in fishkeeping.  

A common mistake for beginners (new tank syndrome) is either not knowing about the nitrogen cycle or not keeping it in mind when maintaining the water.

What Is An Aquarium Nitrogen Cycle?

The nitrogen cycle is the process by which beneficial bacteria convert fish waste and uneaten food in the aquarium into less harmful substances. The cycle is crucial for maintaining a healthy and stable environment for fish and other aquatic animals.

In new aquariums, there may not be enough bacteria to break down fish waste, resulting in an unhealthy buildup of ammonia and nitrite. This is not visible to the naked eye, so it’s important to regularly test the water with a kit to ensure the smoothness of the nitrogen cycle.

What Happens If I Don’t Complete A Nitrogen Cycle?

Failing to complete regular nitrogen cycles can lead to the accumulation of harmful substances like ammonia and nitrite. These substances can cause stress and damage to fish, leading to health problems and if left unchecked it will eventually kill everything in your aquarium.

By maintaining a healthy nitrogen cycle, you can ensure a long and healthy life for your fish. 

Tanks Size

The tank size for a Mbu puffer is 500 gallons at a bare minimum. If you want your Mbu puffer to live a happy healthy life 1,000 gallons is recommended.

Owners usually opt for custom-made aquariums. Since this fish can grow to a considerable size, ample swim space is more crucial than the total tank volume. Therefore, it is essential to consider the dimensions of the aquarium carefully.

Water Parameters

You’ll want to replicate the Mbu puffer fish’s natural habitat as accurately as possible. They prefer warm environments with slightly acidic water and moderately low water hardness levels.

Puffers are also highly sensitive to changes in their water conditions. Maintaining the right environment is extra important to keep them healthy.

  • Water temperature: 75°F – 79°F (24°C – 26°C)
  • Water pH levels: 7.0 to 8.0
  • Water hardness: 10 to 25 KH

What To Put In The Tank

You’ll want to mimic their natural habitat and keep the decorations minimal. Create an environment where they can swim happily and hide when they need to feel safe.


A fine-grained sand substrate is ideal for MBU puffer fish. It is easy to clean and allows the fish to forage and burrow in the substrate. 


You can add some smooth rocks and small pieces of driftwood on top of the substrate to create hiding places for your Mbu puffer. Make sure you avoid anything with sharp edges.

Pebbles and gravel should also be avoided as these could pose a risk to the fish’s delicate skin.

Ideal Plants:

Rooted plants like java fern and anubias are ideal for Mbu Puffers. Although, it’s important to note that these fish can be somewhat destructive, inadvertently crushing plants with their tails as they brush past them or while feeding on food that has fallen onto the leaves.

MBU Puffer Tank Mates

Due to their aggressive nature towards other fish, Mbu Puffers are best kept alone. Fortunately, these fish are content to live on their own and don’t require the companionship of other fish.

While some keepers may suggest that the Mbu puffer can coexist with peaceful fish as long as they don’t compete for the same food, it’s essential to exercise extreme caution. After all, no fish wants to end up on the receiving end of the Mbu puffer’s formidable beak.

MBU Puffer Food & Diet

MBU puffers are carnivores. They need a meat-based diet to be healthy. Their sharp beak-like mouths are made to fit this diet. The healthiest diet for your puffer is one of mollusks. This is what they would naturally hunt in the wild. 

The best foods for your pufferfish are:

  • Snails
  • Worms
  • Shrimp
  • Clams
  • Crabs
  • Mussels
  • Crayfish

Basically, almost any crustacean or invertebrate could be on a puffer’s menu. MBUs are also quite big, so they need lots of food to stay healthy. Feed your Mbu puffer fish 6-8 oz  (170.09-226.79 g) of mollusk meat a day. 

You should also periodically include the shells. Like rodents, their teeth (or beak) never stops growing. They chew on mollusk shells to grind them down. You don’t need to include shells with every meal, but try to provide them at least 5 times a week.

Puffers have a hunting instinct that’s triggered by motion, so live feeding is advisable. Be careful with live mollusks as some may carry parasites. Buy them from a fish store and avoid wild-caught ones. If you decide against live feeding, make sure you wiggle your dead mollusk to catch your puffer’s attention. 

You should also remove sharp pieces from the mollusks’ shells. For example, claws on shrimp and crayfish. This is because sharp pieces can damage your puffer’s delicate skin.

Breeding MBU Puffers

Currently, all Mbu puffer fish available in the aquarium trade are wild-caught, as we have yet to develop the capability to breed them in captivity. This is due to the difficulty in replicating their ideal breeding conditions within an aquarium setting. However, some breeders are actively working towards bridging this gap, with the hope of producing healthier puffers for aquarium enthusiasts to enjoy.

MBU Puffer Common Health Issues 

Mbu puffers have a slightly higher risk of disease potential compared to captive-bred fish. This is because it’s impossible to track their history before they were caught.


Like many fish, puffers can catch white spot ich. As many experienced fish keepers may know, ich is highly treatable, so if your puffer catches it, don’t panic.

Ich Symptoms

  • White spots: The most noticeable symptoms are white spots that appear randomly scattered across the body, fins, and gills.  Keep in mind, this may start out as one single white spot, so monitor your fish closely.  If the spots increase and start spreading, it will almost certainly be Ich.
  • Keep in mind if your fish are bright colors, spotted patterns or have big fins, it is going to be significantly harder to detect the white spots.
  • Breathing Faster: When Ich infects the gills, it can make it harder for your fish to breath. When this happens it causes their gills to work harder and move faster than usual to compensate for the difficulty in taking in oxygen.
  • You may even notice your fish rise to the tank’s surface to make use of the oxygen.
  • Lethargy: As the infection progresses, you will notice your fish will become lethargic and move around the tank slower than they normally would.
  • Loss of appetite and color: As the infection progresses, your fish will lose its appetite and in some cases its color will become paler.
  • Brushing up against objects: These white spots can become very itchy.  When this starts to happen you’ll notice your fish start to brush up against objects to relieve the itching.

Ich Treatment

Test water quality: You need to ensure your water quality is in great shape.  Get a good test kit and test levels for pH, Ammonia, Nitrite, Nitrate, KH, and GH. If anything is out of the ordinary, get onto it immediately.

Raise the water temperature: This will shorten the life cycle of Ich. It is recommended to increase the temperature to at least 86 degrees (30 celsius), and ensure you don’t exceed 90 degrees (32 degrees celsius). Before you raise the temperature, make sure other species in your tank are able to cope with the increase. 

If you have established that all species can cope with the rise in temperature, only increase it by 2 degrees every twelve hours.  Once you have reached the desired temperature, leave it at this level for at least 2 weeks. After 2 weeks, slowly reduce the temperature back down to its normal state.

Add commercial medications: Sometimes adding medication is your only option. Make sure you:

  • Remove all forms of chemical filtration before adding the medicines.
  • Transfer your fish to a quarantine tank before medicating.
  • Read the directions and use a calculator to work out the dosage required.

Ich Prevention

Ensuring you quarantine all the fish you buy before adding them to your main tank is the best way to prevent Ich.

Why Do Puffer Fish ‘Puff?’

The reason why pufferfish don’t have scales is to give their skin more elasticity. This elasticity is why they can perform their signature ‘puff.’ Puffing is a defense mechanism. In the wild, expanding in size scares away predators and makes the fish difficult to swallow. 

Your pet puffer may puff at some point in their life. They’ll do this if something spooks them or when startled. Occasional puffing isn’t dangerous to the fish, but you should try to minimize its frequency. If your puffer is puffing a lot, that probably means they’re stressed out. Stress can lead to other health issues. 

Sometimes, puffers will puff up to get your attention. If there’s no obvious sign of stress and your puffer inflates, they might be trying to tell you something. Perhaps, they’re hungry, bored, or stressed about something that isn’t obvious, like poor water conditions. 

Too much puffing can be harmful. Never intentionally try to make your puffer puff. Stick to finger following if you want to impress your friends with your trainable fish. Many wildlife advocates criticize divers for intentionally making wild puffers puff.

Contrary to popular belief, puffers don’t “hold their breath” to inflate. Instead, they gulp a large amount of water to stretch out their stomach. Frequent puffing wears down their bodies, making them more susceptible to health problems. 

Are MBU Puffer Fish Poisonous?

All puffer fish are poisonous, including Mbu puffers. In fact, puffer fish are one of the most poisonous fish species in the world. This doesn’t mean owning an MBU is inherently dangerous. However, it is one of the many reasons why this fish isn’t for novices. Handlers need to know what they’re doing.

MBU puffer fish are poisonous. All puffers produce a class of toxins called tetrodotoxins. Tetrodotoxins are an incredibly powerful neurotoxin, chemically similar to the venom of a blue-ringed octopus. 

Puffers emit higher amounts of this toxin under stress. In this sense, keeping your fishy friend healthy is as much for your sake as it is for theirs. They also synthesize this toxin with environmental bacteria, so regular tank cleaning may help reduce your risks.

If you think you’ve been infected with tetrodotoxin venom, call emergency services immediately. Symptoms of tetrodotoxin poisoning include:

  • Numbness
  • Intense headaches
  • Nausea
  • Vomiting
  • Loss of coordination
  • Weakness
  • Abdominal pain
  • Paralysis
  • Cardiac arrhythmia 

I don’t mean to scare you away from Mbu puffer fish ownership. However, it would be irresponsible to ignore this reality of the species. As long as you do your research, ask lots of questions, and follow proper care guidelines, you can enjoy many safe years with your fishy friend. 

Puffer Fish Alternatives

Puffers are great pets for the right owner. However, they aren’t the right fit for everyone. If their needs are beyond your capacity but you want to enjoy an affectionate aquatic companion animal, there are easier alternatives:


Like puffers, pacus are known for having a dog-like playful, affectionate personality. The pacu is the herbivore cousin of the piranha. They have a similar appearance without the same level of aggression. They aren’t beginner-level fish, but they are easier than puffers.


Oscars are known for greeting owners when they enter the room and splashing the surface of their tank when they want food. They also have long lifespans of 10-20 years. They’re a type of cichlid, so many standard cichlid care needs apply to them. 


Surprisingly, crayfish are interactive and playful with their owners. Their care needs are relatively easy compared to puffers and pacus. The only issue with them is that standard-sized crayfish don’t do well with tank mates. Dwarf crayfish can be an alternative if you want to keep one with other fish.


There’s a good reason why betta fish are one of the most popular aquarium fish in the world. They have beginner-friendly care needs and loads of personality. Males can be territorial, but they do work with some tank mates. Many bettas will happily swim to the glass to greet their owners and exhibit lively play habits. 

Wrapping Up

Mbu puffer fish are intelligent, affectionate, and interactive with their owners. This behavior makes them an attractive pet for fish enthusiasts who want a marine companion animal. However, they aren’t for casual keepers. 

Only get a puffer if you have a lot of fish experience, and both the space and financial means to give them proper care. Due to their poison, this is for both your and the animal’s safety.

I’m Elle, the founder of FishHQ. I created this website to share knowledge, tips, and inspiration for beginner hobbyists to help them create a healthy, happy, and vibrant environment for their fish to thrive. Read more...