Skip to Content

Clownfish And Seahorses: Can They Live Together?

Disclosure: When you purchase something through my affiliate links, I earn a small commission. As an Amazon Associate, I earn from qualifying purchases.

There is no doubt that both seahorses and clownfish are incredible creatures. As a fish owner, there was nothing I wanted more than keeping them in the same tank. However, my intuition told me that seahorses could be too gentle for clownfish. Can the two actually live together? Well, to answer that, I began researching the topic profoundly.

Yes, clownfish and seahorses can live together, although keeping them in the same tank is not recommended. While seahorses are apathetic, clownfish are rapid, territorial, and aggressive. That poses a severe competition over food, resulting in a stressful, unhealthy environment. 

However, as we move forward in this article, I will show you a few techniques you could implement if you wish to keep both species in one aquarium. That includes a useful DIY aquarium divider, followed by a step-by-step, detailed video.

Also Read: Clownfish Care Guide

Can Clownfish Live With Seahorses?

This isn’t the sort of question you could have asked several years ago. For the longest time, aquarists avoided seahorses because they were famously difficult to keep in an aquarium. Most people who succeeded in netting seahorses in the wild couldn’t keep them alive for more than a few months.

However, aquarists have since cracked the code. They now know what it takes to keep seahorses alive in an aquarium, which is why some beginners have started to wonder whether or not seahorses can live with clownfish.

As far as their relationship with clownfish is concerned, seahorses and clownfish can live together. However, it isn’t recommended, and for quite a few reasons:

1. Stressful Conditions

Seahorses are slow-moving creatures. This is why their tanks usually feature a slow water movement. They are a gentle, cautious species. Clownfish are the opposite. They are fast swimmers, and that alone is going to present a challenge for your seahorses. 

The clownfish are likely to become a source of stress for the seahorse. That issue turns more serious when facing the fact that chronic stress could lower the seahorse’s immune system.[1] That may result in sick seahorses with a much shorter lifespan.

If you are keeping a group of seahorses, diseases could spread through the tank pretty quickly, eventually getting to the entire tank mates. Hence, if your clownfish seem to be swimming rapidly in the seahorses’ zone, it may indicate you should separate the two immediately. 

2. Competition Over Food

Seahorses feed on algae and small crustaceans like copepods.[2] But the problem is that they are not aggressive hunters. In other words, if you put them in a race for food with most other tank fish, they will lose.

If you spray food all over your tank, don’t expect your seahorse to fight other fish for it, they eat really slowly.[3] Clownfish, on the other hand, have aggressive tendencies. They won’t hesitate to bully their tankmates during mealtimes. They are likely to eat all the food you have added to the tank before the seahorse can reach it.

In other words, a tank with clownfish creates a risk of starvation for your seahorses. Unless you squirt the food directly to the corner of the aquarium (an area with a low current), they have no way of securing their meals. That will not happen in a tank with clownfish.

3. Possible Aggression

While clownfish can coexist peacefully with other creatures, they have territorial tendencies. If a seahorse wanders into clownfish territory, it will probably get hurt. This happens all the time in aquariums. 

However, most other fish that wander into clownfish territory have the physical strength and speed to retreat in the face of clownfish aggression. They do this before suffering any severe harm. Some of them can even fight back. 

But that does not apply to seahorses, which do not have scales. As was mentioned above, they are far more vulnerable to physical injury than ordinary fish. Clownfish could seriously harm them if a conflict ever erupted. And clownfish tend to get more territorial the older they become.

For the most part, you are better off keeping clownfish and seahorses in separate tanks. Seahorses are difficult enough to maintain as it is. They require so much care and consideration. Adding clownfish to the equation will only make a difficult situation worse.

Can You Force Seahorses and Clownfish to Coexist?

With aquariums, nothing is impossible. If you try hard enough, you can force most tank creatures to coexist. That is especially true if they require the same water conditions. Luckily, that is the case with clownfish and seahorses. 

Generally, if you have chosen to pair seahorses with other fish, you are encouraged to find slow, docile species that are less likely to compete with them. But if you are determined to keep clownfish and seahorses in the same aquarium, these are the approaches you should take:

1. Consider Separation

Place a barrier in your tank, one that forces your seahorse and clownfish to stay on opposite sides. A lot of people push their clownfish and seahorses to coexist because they cannot afford to purchase a separate tank for either species. 

In such situations, a barrier will guarantee peace in your tank. It will keep your clownfish and seahorses away from one another. You could get one at the pet store for a reasonable price, although I suggest making one on your own. 

Here is a useful video I came across on YouTube, which explains how to make an aquarium divider by using accessible, low-priced materials. That could also be a temporary solution. If you get the sense that your fish are willing to get along, you could remove the divider at any given time. 

2. Get the Right Tank

If your clownfish keep attacking your seahorses because the seahorses keep crossing into their territory, you should get a bigger aquarium. Get one that will reduce the frequency with which the clownfish and seahorses interact with one another. 

One that I would seriously consider is the NUVO Fusion Lagoon 25 Pro (link to Marine Depot). I haven’t purchased it myself, although all the reviews I read regarding that bundle were 5-start positive. It is a well-built bundle that features the perfect size and design for a frag tank.  

What I would do in this tank is put the coral or anemone on one side, avoiding placing it in the middle. That will force your clownfish to accommodate their size while leaving room for the seahorses to swim on the other side. 

3. Watch for Warning Signs

First and foremost, any aggressive activity between your clownfish and seahorse should worry you. This isn’t always the case with other fish. Clownfish, for instance, will happily fight one another. However, they do so only as a means of establishing a hierarchy in their school.

That being said, this attitude does not apply to seahorses. Any sort of conflict between seahorses and clownfish should compel you to act. As was mentioned above, the creatures do not have scales. That makes them more susceptible to injury.

Such a behavior could be a clownfish chasing its companion seahorse, or merely nipping on its tail once in a while. You may start noticing split fins, changes in behavior, and sometimes even wounds.[4]

However, the presence of conflict between your clownfish themselves shouldn’t concern you. This is also true for various other species. Fish are more than capable of chasing one another and nipping at each other’s fins without causing any serious harm. For some species, aggression is a crucial part of their mating rituals. 

One example is angelfish, which can lock lips both as a sign of courtship and a means of dominating one another. I have even dedicated an entire article to that phenomenon, explaining in which cases lip-locking could merely suggest mating purposes. 

4. Stick to Captive Bred Seahorses

When it comes to purchasing seahorses, prioritize captive-bred specimens. Seahorses that were caught in the wild are more delicate. They are also more likely to reject your food, and their bodies tend to resist some medications. 

However, captive-bred seahorses are hardier.[5] If you can get them in good condition and a decent size and age, they are more likely to survive the bullying and the stress they will get from clownfish. Also, look for specimens that are at least four months old and 3 inches in size. 

Smaller, younger seahorses are more sensitive to the shocks of a new environment. Don’t be surprised if a few confrontations with your clownfish ruin their health. A healthy, hardy seahorse won’t make your clownfish any less aggressive. But it will live longer, giving you more time to bring the clownfish under control.

5. Rearrange Your Aquarium

Clownfish are peaceful where their relationship with other species is concerned. They will fight one another to determine the pecking order, but they are not known for bullying other fish, especially if those fish are equally non-aggressive.

Clownfish primarily act out when they develop territorial tendencies. This happens a lot when you allow two of them to pair off. They won’t hesitate to attack any seahorses they perceive as a territorial threat. The fact that seahorses have no interest in claiming territory is irrelevant.

One way of resolving this issue is to rearrange your aquarium. Turn the lights off and move some things around.[6] This will essentially eliminate your clownfish’s territory, leveling the playing field and forcing all the creatures to establish themselves anew. 

This favors your seahorses because they can claim a new corner of the tank for themselves without accidentally crossing into clownfish territory. As was mentioned, if your tank does feature an anemone, make sure that you rearrange it to the other side of the tank. 

It is also essential that your clownfish choose to host in your anemone. That will prevent them from swimming around and encountering your seahorses. For your convenience, here is an article I’ve written on how to make clownfish to be hosted by anemones. That includes a few steps that are highly effective and incredibly easy to implement.

6. Put Some Plants and Decorations

Make sure your aquarium has plenty of hiding places. Add plants and decorations that seahorses can use to steer clear of your clownfish. This is one of the most effective methods of keeping the peace in a tank populated by a mix of docile and aggressive fish.

Clownfish, like most fish, do not hold grudges. They have no interest in hunting down and antagonizing their tankmates. If your clownfish can’t see your seahorses, they will leave them alone. Seahorses, for their part, are always looking for objects that they can wrap their tails around to keep them in place when they are not hunting. 

If you can give your seahorses hitching posts in some distant corner of the tank that your clownfish rarely traverse, they should be safe. However, make sure not to place them next to the filter. Harsh currents won’t do any good to your seahorses. 

7. Consider Isolation

If a particular clownfish is causing most of the trouble for your seahorses, do not hesitate and isolate it. Place the troublemaker in a net breeder. Keep it in one section of the tank where the aggressive clown can see the seahorses but cannot attack them. 

More than keeping troublemakers out of the way, this approach forces both the clownfish and seahorses to grow accustomed to one another. After a few days, you may release your clownfish and see what happens. If its behavior hasn’t changed, isolate it once again. 

Conclusions

While clownfish and seahorses could generally live in the same tank, as a fish owner, you should avoid that approach. That is because clownfish are swift and aggressive, while seahorses are docile, slow swimmers. High amounts of stress and competition over food may end up with a sick seahorse.

If you wish to keep them in the same aquarium, you could get a large tank (at least 25 gallons), while placing the anemone or coral at one corner. You could also use a barrier, eliminating all potential encounters between your clownfish and seahorses.

I hope my article has shed some light on your questions. If you have any hesitations, feel free to reach me via the contact page. In the meantime, I hope you will be able to enjoy your aquarium and what it has to offer. 

References

  1. https://seahorse.com/seahorse-stress-disease-health-problems/
  2. https://www.petmd.com/fish/care/guide-keeping-healthy-pet-seahorses
  3. https://www.wikihow.com/Choose-Good-Tankmates-for-Seahorses
  4. https://www.ratemyfishtank.com/blog/aquascaping-tips-to-reduce-aggression-in-fish
  5. https://blog.marinedepot.com/2018/06/secrets-for-success-rules-you-should-follow-to-keep-your-seahorse-aquarium-thriving.html
  6. https://aquariumsphere.com/how-to-deal-with-aggressive-fish-in-aquarium/