Freshwater Amazon Puffer Fish Care Sheet

Many saltwater fish families have evolved to live in freshwater and brackish water environments worldwide. One of them is the pufferfish species (family Tetraodontidae). However, only a few aquarium hobbyists are inquisitive about these species as pets.

Several species of truly tropical pufferfish inhabit freshwater streams in Asia and Africa, such as the pea puffer. However, there is one of the “oddball” freshwater pufferfish species, found only in South America.

Are you curious about this one?

In this article, we will share all information about these pufferfish species, starting from A-Z. If you are looking for quick information about them, you can see the table of contents below. Keep reading if you want to learn more deeply about these pufferfish.

Amazon Puffer Care Overview

• Care level: Intermediate
• Minimum tank size: 40-gallon
• Temperament: Peaceful and sometimes becomes fin nippers
• Lifespan: 10 Years
• Diet: Carnivore
• Temperature: 72.0 – 82.0° F
• pH: 6.0 – 7.5
• Size: 8 cm (3.1 inches)
• Family: Tetraodontidae
• Genus: Colomesus

Species Overview And Origin

The freshwater South American pufferfish (Colomesus asellus) is usually called Amazon puffer, Peruvian puffer, SAP, Bee puffer, Bumble Bee pufferfish, Brazilian puffer, Asell’s puffer, and asellus puffer. C. asellus was first described in 1849 by Müller and Troschel. They are unusual freshwater pufferfish native to the Amazon, Orinoco, and Essequibo basins in tropical South America.

According to a 2013 study, a population exhibits a similar appearance to C. asellus in the Tocantins River basin, but differs genetically. These species are known as Colomesus tocantinensis. Now, there are two freshwater pufferfish species that originate from South America.

Locals commonly refer to the Amazon pufferfish as “pez globo.” They typically live in open water habitats, mostly found around sandy shallows. These pufferfish are also found in other areas, including beaches, banks with abundant vegetation, and floodplain lakes.

The Amazon puffer prefers fast-moving water that is richest in oxygen-dissolved water and contains many crustaceans and mollusks, making them its favorite foods. These puffers may be sensitive to low oxygen levels. The water hardness that they can accept includes soft, slightly acidic, or hard.

Some aquarists believe that these puffers can tolerate brackish water. Some populations adapt well to the upper Amazon’s tributaries. They tend not to be found in blackwater environments, which are characterized by highly acidic conditions.

The South American pufferfish is ideal for an experienced aquarist looking to keep an exotic fish and create a unique atmosphere in their tank. These species are rare to find in the trades, so the price is relatively high. A single healthy adult Amazon pufferfish typically sells for $30 or more.

Amazon Puffer Fish Appearances

Colomesus asellus typically grows up to 8 cm (3.1 inches) in the wild; however, in the aquarium, it may be significantly smaller. They have a yellow-green tint at the upper parts of their bodies, and the bellies are white, but they have different patterns.

Amazon puffers also have five dark stripes that run across the upper part of their body. One above the eye, one behind the eye, one under the dorsal fin, one behind the pectoral fin, and one ring right before the tail fin. These stripes may vary in pattern between individuals.

On the internet, you may find another pufferfish closely similar to C. asellus. Colomesus Psittacus (banded puffer) is a brackish puffer species that grows larger than them (grows up to 14 cm). The most prominent distinguishing feature between the two sexes is that C. asellus has black spots on the underside of the caudal peduncle, while the other one does not.

The banded puffer also has extra back stripes and smaller eyes. These brackish puffer species are also unpopular, so you might not find them at the average aquarium shop.

An interesting fact about the Amazon puffer fish is that it is a species that can blink and close its eyes. They do not have pure teeth. Instead, a jawbone acts like four tooth structures that grow continuously and quickly. So, the food with hard shells, such as snails or shellfish, could help to ‘trim’ their jawbone down. Because if it develops overgrown, these puffers would not consume their food and may die.

Sexual Dimorphism

Differentiating between the male and female sexes is quite challenging.

Amazon Puffer Fish Behavior And Temperaments

Keeping Amazon pufferfish is fun. They are intelligent and a very curious species. If there is an unusual thing in their tank, they will investigate it quickly and observe it closely with their large eyes.

When the keeper gets associated with them, they will beg for food if they are hungry without feeling shy. These freshwater fish are relatively active. You will see them swimming the length of their tank.

If the Amazon puffer becomes stressed, it will exhibit erratic swimming behavior, known as “glass surfing.” Sometimes, they stare at the glass, which means these fish feel bored. So, you can add a new decoration to their tank to raise their curiosity.

Unlike most tetraodon families, these puffers are not aggressive and non-territorial toward tankmates and live well in mixed-species aquariums. In fact, they are more suitable for keeping in small groups, ideally about three members or more.

If you take care of only a single Amazon puffer in the aquarium, it is commonly nervous. However, placing them in large groups is not the right approach if the space is insufficient. It precisely makes these fish easily restless and scared.

Sometimes, the larger one might bully the smaller fish, but this rarely occurs and usually happens in a short period. To resolve the bullying problem between each other, adding some specimens will make it difficult for any fish to become more dominant in groups.

Although they perform well in groups, the Amazon puffers swim together with other members only for a short period before every individual decides to do their own thing for a while. When night falls, all members will gather together to sleep in the same place in the tank.

In their habitat, they generally spend a lot of time swimming in open water or exploring the surfaces of aquatic plants and stones, while entering caves is rarely done. When sleep time comes, they tend to choose a patch of fine gravel or sand, planted with robust plants such as the Amazon sword, as a resting place. Unlike Asian species, South American pufferfish are infrequently known to dig into the substrate.

Amazon Puffer Fish Lifespan

However, the Amazon pufferfish bodies are smaller than those of other fugu species, but their lifespan is longer, reaching up to 10 years. The mix of genetics and quality can affect their average lifespan.

If you do not provide the Amazon puffer with the optimal quality care it needs, achieving a ten-year lifespan is impossible. By following the step-by-step instructions in this article, your fish may grow healthier and live longer.

Amazon Puffer Housing & Tank Setup

According to the statement above, this fish will thrive in small groups or communities. For taking care of Amazon puffer in the aquarium, you need a 40-gallon tank to accommodate 3-4 fish. You are providing them with more space in the tank, helping them thrive more easily and maintain their environment because they are active swimmers and messy eaters.

Using sandy substrate or fine gravel is better; it resembles a natural substrate in their wild habitat. Use a high-nutrient substrate to increase the growth of aquarium plants. These puffers are very appreciative of the lush plants in their tank. The fine substrate (such as Fluval black sand) can also grip the roots firmly, making your plants stand sturdy.

Planting some aquatic plants helps enhance the Oxygen dissolved in the planted tank; it’s very critical if it is not present. It would be best to grow aquatic plants with thick and heavy leaves, such as anubias species, cryptocoryne, Cabomba, etc.

Adding extra floating plants serves to shade areas in the aquarium suitable for the Amazon puffers when they feel nervous. They may also become an interesting object to observe for those.

You can add a few decorative items, such as rocks or wood, to the tank. Do not over-place hardscape. These puffers prefer open water for their activities.

A high-quality filtration system is essential. You can set it medium-high for water flow. Amazon puffers often leave leftover food or feces at the bottom of the aquarium, so you will need a filter that can effectively siphon it out.

There is no specific requirement for the lighting system, but you can set it to a low to medium level. Using a heater is optional. Every place has a different temperature, as well as varying water conditions. So you can fit it with the conditions where the aquarium is placed.

If you need a specific water parameter that is suitable for Amazon puffers to live in, here’s what you need:

• pH level: 6.0 – 7.5
• Water Temperature: 22.2 – 27.8° C (72.0 – 82.0° F)
• NO3: < 15 ppm
• Water Hardness: 5 – 20 dGH
• Brackish Tolerance: Sometimes – Up to SG 1.005

Amazon Puffer Fish Care

As we know, the Amazon puffer can survive in a wide range of water in the wild. However, a crucial aspect to consider when caring for them is the quality of the water. It means the water needs to be recycled frequently to ensure it is far away from nitrate and ammonia.

The South American puffers lack gill covers and scales, making them more susceptible to diseases. Then, they have lousy behavior. They often leave a few parts of their food in the aquarium (messy eaters), which affects the water quality and places an additional load on the aquarium filtration.

To address this issue, perform a water change of approximately 30% to 50% of the tank’s volume every week. It is a standard rate for a puffer tank. You will require a larger canister filter to recycle the water 6-10 times per hour. It is best to test the water regularly with a liquid test kit, even if you think the water quality is acceptable.

The bumblebee puffers are particularly sensitive when entering a new tank. Ensure that you provide optimal conditions that these fish require in your tank.

Amazon Puffer Fish Tankmates

Unlike most puffer species, the South American puffers are suitable for community aquarium settings. They are peaceful and tolerant of the non-aggressive species. However, sometimes they can still be annoying to the long-finned, passive, and slower-moving species, although this is commonly only at feeding time. Therefore, these fish are not recommended to be kept together with long-finned tetras, guppies, and angelfish.

The larger, territorial, and aggressive species, such as larger gourami species, must be avoided. The puffers may get bullied by them. Small, faster bottom dwellers like corydoras are better options for their tankmates. Although they move quickly, they might still get fins nipped by the Amazon puffers.

You can also keep them with short-finned and fast-moving species, including larger rasboras, rams, garra rufa, SAE, mollies, platies, medium-sized characins, Apistogramma, hatchet fish, and glassfish. On the other hand, crustaceans and mollusks, such as zebra nerite, should not be used as tankmates for Amazon puffers because they might be hunted as snacks.

Amazon Puffer Fish Diet And Feeding

Colomesus asellus is carnivorous. In its natural habitat, it hunts extensively for smaller creatures, such as crustaceans, larvae, and snails. In the aquarium, you can feed them with snails, cockles, or crab legs to maintain their jawbone (teeth-like) to help it overgrow.

Other foods that they accept include chopped shellfish, Artemia, bloodworms, earthworms, frozen shrimp meat, and other live or frozen fish food. Conventional dried products, such as pellets and flakes, may be accepted or rejected, depending on the individual fish. The aquarium parasites, such as detritus worms or hydra, may be eaten by them. However, green hair or staghorn algae will be unacceptable due to their carnivorous habit.

Amazon Puffer Fish Breeding

Unfortunately, it is not possible to breed the C. asellus in home aquaria or captivity. The Amazon puffer fish’s breeding behavior is identical to that of most marine puffers. They produce tiny eggs in large numbers, and the fry should pass through a planktonic phase. The fatal thing is that Amazon puffer fish do not build nests and do not participate in taking care of their babies, making them difficult to breed manually.

When the wet season begins in their natural habitat, the female and male puffers congregate in large river streams to release their eggs and sperm into the water. According to limited studies, the spawning session typically occurs in primary river channels, tributaries, and on the banks of floodplain lakes at their mouths.

Once the fertilized eggs hatch, the fry that appear may be carried by the water flow into a specific nursery zone, where they will then develop. In this period, the fry may consume planktonic organisms around them to survive.

The metamorphosis process may take a couple of days. When they are strong enough to swim, the young Amazon pufferfish will actively swim against the current. The parents will return to the river channels when the breeding season is over (usually when the floodwaters recede).

Common Diseases That Can Infect Amazon Pufferfish

White spots and fin rot are common diseases that usually attack South American pufferfish. Actually, they are hardy fish, but they might be prone to sickness if you keep them in poor conditions. Please provide them with the best tank environment they need.

Generally, the Amazon pufferfish responds well to medication and recovers quickly. API Super ICK CURE is the best solution to fight whitespots, and API FIN & BODY CURE is believed to treat the fungus and finrot effectively.

Adding aquarium salt, at a rate of three doses per liter, and raising the water temperature to around 28-30 degrees Celsius may be an alternative way to kill parasites without harming the fish in the long term. Once your fish is completely free from disease, perform a water change and reduce the temperature to the standard (around 25 degrees Celsius).

Another health problem associated with the Amazon pufferfish is excessive tooth growth. The first method to prevent their teeth from overgrowing was shared above. Now, the second method is manual. This process is simple: take 1 liter of aquarium water into a box, add two or three drops of clove oil, and stir it.

Next, catch your pufferfish using a net and put them into an oil bath until the fish calms down. After that, grip the puffer softly using your hand and trim its points of jawbone-like teeth using cuticle clippers in your other hand.

Then, drop the puffer into the net again and carry it back to the aquarium. Hold them still in the net until the fish become active again. This process may take a few minutes to complete. After that, you can release your fish back into the tank, where it will swim happily. Most aquarists usually trim their Amazon pufferfish’s teeth one or more times per year.

Are The Amazon Pufferfish Poisonous?

Yes, Colomesus asellus is poisonous if consumed as food. Their toxin (saxitoxin) is accumulated in their flesh. This poison is produced by certain bacteria and algae that grow on a specific type of shellfish.

The venom in the Amazon pufferfish fluctuates throughout the years, depending on how many components are produced by the toxins they eat. Without access to the poisonous diet, the wild-caught South American pufferfish will lose their venom.

So, do not panic since you never eat your pufferfish. You will be safe. The pufferfish kept in an aquarium for a long time is commonly free from toxins because its owner usually controls the quality of its diet.

Do Amazon Pufferfish Puff Up?

Sure, they can inflate their bodies several times larger than normal by absorbing water or air. They perform it when they sense danger or scare predators to make themselves difficult to catch. But never make them puff up deliberately by lifting them from the tank by hand. It causes the puffer’s stress, which is detrimental to them.