Can Seahorses Be Kept With Puffer Fish? Full Compatibility Guide.

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Seahorses preferably require a species-specific aquarium with no other tankmates, however, under the right circumstances, seahorses can be safely kept with quite a variety of fish and invertebrates.

We’ll discuss puffer fish to check whether these fish are suitable tankmates for seahorses and if it is safe to form this pairing duo.

Pufferfish are not compatible tankmates for seahorses and should never be kept in a seahorse aquarium. They may look cute and colorful but they are surprisingly temperamental and are known for biting the fins of slow-moving tankmates. Their ferocious disposition deems this type of fish unsuitable for sedentary fish like seahorses.

Pufferfish aren’t even considered reef safe and stand no chance as possible tankmates for seahorses.

They are way too aggressive and solitary to be trusted with other marine life that is not within their disposition.

While some species are tolerant and may be accommodating when young, seahorses would still stand no chance as possible inhabitants since these guys are really smart and they prey on slow-moving fish.

Seahorses are the kind of fish that these bad guys prey on and having them share a small closed-system is a recipe for disaster.

You should never try to pair these two fish as they are not compatible at all, it’s safest to keep them separate in individual aquariums that cater to their needs.

Why Are Puffer Fish And Seahorses Not Compatible?

When pairing fish there are many factors that come into consideration to make sure that the tankmates they will be living with are compatible.

Pufferfish and Seahorses are not compatible for many reasons, let’s take a look.

1. Different Natures

Seahorses are very inactive docile fish that are almost defenseless, while pufferfish are quite the opposite.

Puffers are known for their predatory aggression and their territorial tendencies.

This huge gap between dispositions leaves much room for error if these two creatures were to be paired within the same tank.

The fast-paced movements and interaction of the puffer would be sufficient to cause stress and trauma on the seahorse

And as you know only the strong survive leaving these ponies hopeless with a death wish that’s beyond their control.

2. Difference In Eating Habits.

Puffers are predatory fish that plans their prey and target possible advances. This intense precision to meal times can easily outcompete the delicate feeding nature of seahorses.

Seahorses remain inactive and eat passively, they are the type that sits and waits for the food to pass them by so they can access it.

While puffers use their excellent sight to scout food or detect predators early. These guys will go out of their way to get what they want even if it’s through aggression.

This difference in eating habits will leave the weaker one ( seahorse) fighting for resources without any real chance of surviving.

3. Aggressiveness.

Seahorses do well in species-specific tanks for a reason. This is because they are easy targets and can fall prey to most marine wildlife.

They are probably the most fragile creature of the ocean hence their high mortality rate.

They do not do well with aggressive tankmates and can easily become compromised if stressed.

The pufferfish are too aggressive and they are willing to attack anyone they perceive as a threat. 

4. Willingness To Co-exist.

Pufferfish are very solitary as they like being alone without the interaction or participation of any other tankmates.

This is enough reason to have them exempt from community tanks and other tanks that involve many tank occupants.

This is the reason why they aren’t categorized as reef safe and will never be able to co-exist with sensitive fish like seahorses since they will be seen as competitors and prey.

Risks Of Keeping Them Together.

While keeping puffer fish and seahorses together is highly unadvised some hobbyists are still willing to take a chance in hopes for a successful union.

These actions do come with a certain level of risk which we are about to speak about.

1. Possibility of seahorses having their fins nipped. As it is seahorses are weak swimmers if their fins become defective or removed they will have no means of propulsion. Leaving them immobile and susceptible.

2. When it comes to feeding, puffers are skilled predators and will outcompete seahorses in every possible way or form. Your seahorses may not get sufficient resources needed for them to survive.

3. Most pufferfish contain a toxic substance that makes them deadly to humans and other fish. In fact, some species of puffers are known as one of the world’s most poisonous vertebrates. Having them with seahorses can be potentially fatal.

4. Pufferfish don’t have scales in fact they have spiky flesh that can harm seahorses quite easily. Any injury, a nip, or even a simple bruise to a seahorse can become fatal leading to infection and their decline.

5. Placing seahorses with such ferocious tankmates is unfair and cruel. These fast-paced swimmers can cause stress and trauma to these docile ponies which in no time can lead to greater destruction to their health and mental wellbeing.

Alternative Ways Of Keeping Them.


Both seahorses and pufferfish are extremely aesthetic and unique making them great tank occupants in just about any aquarium.

Unfortunately, you can’t keep them together, however, you can keep them separately.

This will involve having two tanks which should cater to both species individual needs.

In this way, you get to keep both fish just that it will be kept separately.


If you are not interested in having two separate tanks rather look for other tank occupants that are similar to what you looking for.

For example, if you already have a seahorse aquarium and want to keep pufferfish with them, you can opt for other suitable tankmates instead of puffers.

You can try a goby, royal gramma, or even certain types of clownfish that can be kept with seahorses.

Alternatively, if you already have a puffer fish and want to keep seahorses, you can look for other replacements that are similar to seahorses.

These include fish like Clown plecos which are equally unique but are more suitable.

Aquarium Separators.

Aquarium separators can be a possible solution for you to keep aggressive fish within the same tank as other peaceable fish.

It’s merely a plastic clear wall that can be easily mounted onto the existing tank making clear separation of boundaries.

This can help keep both seahorses and pufferfish in the same aquarium but without the possible dangers.

The aquarium will still remain the same with the water capacity and chemistry just the space will be limited.

Compatible Tankmates For Seahorses And Pufferfish.

Looking for compatible tankmates for seahorses and pufferfish is literally on either ends of the spectrum. On one side we have the cute little defenseless seahorse and on the other end, we have the tough aggressive puffer.

Let’s take a look at suitable tankmates for each of these occupants.

Tankmates For SeahorsesTankmates For Pufferfish
1.  Goby ( Firefish, Purple, Neon)1. Clown Pleco
2. Cardinalfish ( Flame, Pajama)2. Rasboras
3. Dartfish (Red, purple, Exquisite, Helfrichi)3. Mollies
4. Jawfish (Yellow head, Blue dot)4. Bumblebee Goby
5. Dragonet (Mandarin- red and spotted, scooter)5. Neon Tetra
6. Pipefish (Banded, blue stripe, Janss)6. Platies
7. Molly Miller Blenny7. Killifish

Final Thoughts.

Both seahorses and pufferfish are very unique and beautiful marine life, unfortunately, they are possibly the worst tankmates for each other.

They should never be put in the same aquarium unless you have made the necessary changes to accommodate them.

The safest and best way is to find other tankmate alternatives for a more peaceable aquarium.

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