Freshwater Clownfish? Doppelgangers? Can Clownfish Live In Freshwater? 

Mar 3, 2022

Freshwater Clownfish

Finding Nemo did us dirty. First, it got us thinking that clownfish are innocent, peachy little fish. They’re not. Second, it made us assume clownfish can live in a tiny little bowl like a goldfish (we don’t endorse that either). They can’t. 

Clownfish are saltwater fish. And if you’re a beginner dabbling in the hobby for the first time, raising saltwater fish can seem something like walking on eggshells. 

But is there any trick you can pull to acclimate them to freshwater?

Can clownfish live in freshwater? What do hobbyists have to say about it? 

If not, are there any freshwater clownfish alternatives out there?

I’ll answer all of these questions and some more! Keep reading! 

Can Clownfish Live In Freshwater? Is Clownfish Freshwater Or Saltwater Fish?

No, clownfish cannot live in freshwater. This is because saltwater fish have salty water present in their body themselves. And when freshwater enters their body through osmosis, it will cause the fish’s cells to swell and cause its death. 

Clownfish, like all saltwater fish, are accustomed to hypertonic conditions. So if you expose them to a hypotonic solution like freshwater, it would inflate their body cells. And the repercussion is an immediate yet painful death. 

I came across a few blogs and threads on the internet discussing the probability of acclimating clownfish in freshwater. I couldn’t quite figure out if they were serious or trolling, but the aftermath of such a reckless experiment is the death of the fish 10 out of 10 times. 

No matter how long you acclimate the fish or how many generations you raise, a clownfish’s kidneys and gills are simply not built to handle freshwater, and they won’t at least for a couple of thousand years. 

If you are bent over backward to emulate a freshwater tank with similar color schemes, you could try housing fish like kuhli loaches and tiger barbs. I’ve mentioned a couple of them in a segment below. Keep reading to know. 

And if you’re being pressured by your child to create a saltwater tank setup, you can start with a freshwater rift valley system like a Lake Malawi or a Lake Tanganyika tank. 

Several colorful and vibrant fish originating from these lakes easily give marine fish a run for their money.

Now, I will go into the depths of why clownfish cannot survive in freshwater. 

It’s going to be a long explanation, potentially full of jargon. So, you might want to sit down for this. 

Why Can’t Clownfish Live In Saltwater? 

To understand why clownfish cannot live in freshwater, you need to familiarize yourself with terms like osmosis, hypertonicity, and hypotonicity. 

What Is Osmosis?

Imagine a container with 100ml water, and you added about 15 grams of sugar to it. The sugar dissolves in the water. 

So, the sugar is solute, water is solvent, and the sugar-water mixture is the solution. 

Again, imagine you have a second container with 100ml water, and you added about 45 grams of sugar to it. 

Now, you have 2 containers with mixtures of different solute concentrations. 

Here’s the critical bit now. 

The solution with a lower solute concentration is hypotonic. And the solution with a higher solute concentration is hypertonic. 

The first sugar solution is hypotonic to the second solution. Whereas the second sugar solution is hypertonic to the first one. 

Next, imagine that you have a beaker that has been divided in the middle with a permeable membrane. The membrane must be such that the pores are too small for sugar molecules to pass but large enough for water molecules to pass through. 

Add the hypotonic solution to one side of the beaker and the hypertonic solution to the other side. 

Since the hypertonic solution has a lower water concentration than the hypotonic solution, a concentration gradient of water exists across the membrane. 

The water molecules will shift from the higher water concentration to the lower water concentration until both solutions become isotonic. 

The equilibrium is reached at this point. 

What Is Osmosis? I’ll Answer For Real Now. 

Osmosis refers to the diffusion of water molecules across a permeable membrane from an area of higher concentration to an area of lower concentration. 

Pay attention now. 

Water goes into and out of the cells through osmosis. 

If the cell is in a hypertonic solution, it means the solution has a lower water concentration than the cell cytosol. The water moves out of the cell until solutions on both sides become isotonic. 

On the other hand, cells placed in a hypotonic solution will take in water across their membrane until both cytosol and external solution become isotonic. 

A biological cell that does not have a rigid cell wall, like the red blood cell, will swell and burst when placed in a hypotonic solution. 

Now when placed in a hypertonic solution, a cell sans a cell wall will lose water to the environment, shrivel, dehydrate, and probably die. 

Osmosis can have a life-threatening impact on organisms.

Clownfish And Osmosis Regulation

If a saltwater fish like clownfish, whose cells are isotonic with seawater, is placed in freshwater, the fish’s cells will take on excess water, swell up, and the fish will die. 

I’ll touch on the subject some more. 

As you know, seawater has a higher concentration of salt. So, seawater is hypertonic. Therefore, the salt concentration is much higher outside the cell (in the ocean) than inside the clownfish’s cell. 

Therefore, water is constantly being drawn out of a clownfish’s body. 

However, over a billion years, these fish have adapted to osmoregulate by constantly drinking more water than the amount being sucked out of their bodies. 

This helps ensure they always have enough water in their bodies. 

On top of that, a clownfish’s kidneys and gills, like that of most marine organisms, have been specifically designed to filter the excess salt out of the body by urination. 

In the case of freshwater fish, the reverse is true. These fish live in hypotonic environments, meaning the salt concentration in their bodies is much higher than the salt concentration in the water.

Resultantly, water is continuously being drawn into their bodies. And they compensate for this by constantly urinating to prevent the cells from bursting. 

So, the bottom line here is that saltwater fish have to constantly drink water to maintain the balance in their cells. On the flipside, freshwater fish have to continually urinate to avoid bursting. 

I hope it’s clear now. I tried to make it as simple as possible! 

While at it, I combed through at least a dozen different forums and rounded up a few comments on what hobbyists like you and I think about keeping clownfish in a freshwater tank. 

Disclaimer: You may not like the answers! 

Can Clownfish Live In Saltwater? Real Answers By Real People! 

Note: All the responses shared below solely belong to the respective owners. 

“Evolution happens over a larger span than a couple of generations. Their gills would have to change entirely to breathe in freshwater. I don’t think it’s possible.”

“If you keep breeding them in freshwater, maybe in a few hundred years, you can get some clowns that can survive in freshwater through natural selection.”

“Hmm… It is possible. But it can take anywhere from 1 to a billion generations.”

“My clownfish loved the freshwater tank I set up for him. But, unfortunately, he died in about 15 minutes.”

“Nopity nope. You would have better luck trying to breathe underwater.”

“There are fish that can acclimate to changing levels of salinity, but your clownfish ain’t one of them.”

“Research, research, research! Clownfish are not migratory fish. Their slime coat will come right off in freshwater.”

“Is this some kind of troll? I’m not sure if you should be keeping saltwater fish or corals if you gotta ask this question.”

So that’s a big, fat NO from our fellow hobbyists. 

But don’t get disheartened. I have some good news for you.

Although clownfish can’t make it in freshwater, there are some freshwater species that somewhat look like clownfish. 

I’ll be honest – these fish are no clownfish doppelgangers. But aesthetics-wise, they do share a few similar characteristics. 

Freshwater Alternatives For Clownfish 

If you’re really inspired to get yourself a pet Nemo but aren’t committed to spending $1000 or up for a saltwater setup, there are a few freshwater alternatives like tiger barbs, clown loaches, goldfish, platies, and mollies. 

Let’s look at them one by one. 

Tiger Barbs 

Credit: Andre Karwath (CC License)

Intense black stripes against a light orange body and fierce red fins – tiger barbs look nothing short of magnificent. They come in different variations, including albino and even fluorescent colors! 

Remember, tiger barbs are shoaling fish that should at least be kept in groups of 6. And they’re known to be semi-aggressive – often nipping fins of slow-moving, long-finned fish. 

A small shoal of tiger barbs would require at least 30 gallons (114 liters). 

Clown Loach 

Credit: Andre Jakubiz (CC License)

Clown loaches have large orange and black stripes. If Nemo was a loach, this is exactly how I expect him to look! These fish are easily found across all pet stores. 

And mind you, they carry the potential to grow up to 30.5 cm (12 inches) long and should always be kept in groups. So, they’re not meant for small tanks. 

You’d at least need a 5-6 feet tank to house a couple of them together. 

Platies 

Credit: Marrabbio2 (CC license)

Although not striped, platies come in bright orange colors, just like clownfish. Several color morphs are available, including black and white spots against an orange body. 

These livebearers make extremely hardy fish – thus, they’re perfect for beginner fishkeepers. 

They ideally need around 15 gallons (57 liters) of tank space. 

Mollies 

Credit: Gerardeen92 (CC License)

Ornamental mollies come in a plethora of different color combinations. While the most well-known variations are black and dalmatian, there are orange mollies, too. 

Orange mollies are mostly sailfins or sailfin crosses. Hence, they can get quite pretty big – around 10cms (4 inches). 

You will need at least 20 gallons (76 liters) of tank space to keep these fish.

Goldfish 

Credit: Heptagon (CC License)

Goldfish are only second to Nemo in terms of popularity. Although there are no striped goldfish varieties yet, some do come with beautiful white and black marks. 

And by the way, goldfish can be surprisingly high-maintenance. They’re not at all suitable for small fish bowls or beginners as so often marketed. 

These coldwater fish can grow quite big and are known to be messy. 

A single fancy goldfish would require about 20 gallons ( 76 liters) of tank space, while a comet goldfish demands at least 55 gallons (208 liters).

Bumblebee Goby

Credit: Sven Kullander (CC License)

Bumblebee gobies are another beautiful striped fish to add to your freshwater aquarium. 

They don’t exactly look like clownfish but do share a fair share of similarities. The strong contrast between black and yellow stripes makes them stand out in any aquarium.

Bumblebee gobies grow around 4.2 cm (1.7 inches) long and require at least 10 gallons of space per fish. 

Recommended Readings!

Are There Any Blue Clownfish? Real VS Fake Images!

Ocellaris Clownfish Care Guide | Everything You Need To Know

Maroon Clownfish Care Guide: Everything You Need To Know 

Can You Give Clownfish A Freshwater Dip?

Yes, you can give your clownfish a freshwater dip if needed. But you need to tread carefully. Dipping a saltwater fish in freshwater – and vice versa – is often done to annihilate external bacteria and parasites. 

Therefore, when you dip clownfish in freshwater, it will eliminate the external parasites through osmotic shock. 

In short, freshwater will diffuse into the parasites’ bodies – causing them to swell and burst! 

I’ll tell you how to give your clownfish a freshwater dip in 7 easy steps. 

  • Fill a medium-sized plastic container halfway with a suitable freshwater source. If you’re using tap water, don’t forget to chlorinate it first. 

  • Try to emulate the original tank’s parameters in terms of temperature and pH as much as possible to lessen the fish’s stress. 

  • Add a small dose of ammonia-neutralizing agent to the treated water to prevent ammonia buildup. 

  • Although this step is not indispensable, adding a certain dose of antibiotic medicine to the treated water is recommended. That’s because the fish will release some waste in freshwater, which most likely will contaminate it. 

  • You need to keep the water aerated vigorously throughout the treatment. The best method is to place an air stone attached to the aquarium air pump into the container. 

  • Remove the infected fish and place them in newly prepped freshwater. Make sure you don’t overcrowd the container. 

  • The fish should stay in freshwater for 3 to 4 minutes for effective results. But if your fish shows any signs of stress or discomfort, remove it immediately. 

Frequently Asked Questions 

Before we end this article, let’s have a look at some of our most commonly asked questions! 

Can You Recreate A Finding Nemo Marine Tank?

No, it’s not possible to recreate a Finding Nemo-inspired marine tank. At least a dozen compatibility issues will arise. On top of that, fish like Gill, a Moorish idol, can be super tricky to raise in captivity. 

If you are harboring this idea or are being pressured by young children, get your head out of the clouds right now! 

Otherwise, it will be one heck of an expensive mistake. 

Can Freshwater Fish Ever Be Able To Live In Saltwater?

No, freshwater fish such as goldfish and guppies absolutely cannot live in saltwater. If they’re exposed to saltwater, the water inside their body will flush out of their cells. And as a result, the fish will die of dehydration within a couple of minutes. 

However, Australian scientists have recently discovered that goldfish are becoming an invasive species in estuaries with a much higher salinity level than what they’re used to! 

If you’d like to read more on it, here’s the article you should check out. 

Related Articles: Can Goldfish Live In Saltwater?

What Saltwater Fish Can Live In Freshwater?

Some saltwater species can live in freshwater for certain periods. They’re known as anadromous fish. These fish are born in freshwater, migrate to saltwater for the rest of their lives, and come back to freshwater just to lay eggs. 

Examples of anadromous fish are sturgeon, striped bass, smelt, salmon, shad, sea trout, three-spined stickleback, and sea lamprey. 

Final Words: Freshwater Clownfish? 

No, clownfish are saltwater fish. They cannot survive in a freshwater tank. 

When exposed to freshwater, the water enters their body through osmosis, causing the fish’s cells to swell and explode – which is fatal, of course! 

Clownfish, like most saltwater fish, are often given freshwater dip to get rid of bacteria and parasites leached on them. It’s a common practice – and I assume it’s pretty effective too. 

However, if your fish shows any discomfort, you should quickly transfer it to a saline environment. 

And don’t get disheartened. If a saltwater tank is not possible at the moment, there are a few freshwater species that share some similarities with clownfish – whether its iconic stripes or the bright orange colors. 

Recommended Readings!

Clownfish And Blue Tang | Here’s Why It Won’t Work 

What Kind Of Fish Is Dory? Why They’d Make Terrible Pets?

Can You Eat Clownfish? Here’s Why You Wouldn’t! 

rohit gurung author at urbanfishkeeping

About Rohit Gurung

My never-ending love and fascination with Aquascaping started when I received a red-eared turtle for my 10th birthday.

Apart from researching and writing, I spend hours gazing at my 3 turtles. And yeah, I bask alongside them too.