Clownfish

a Clownfish swimming within a sea anemone

Clownfish are great fish to keep in your family’s saltwater aquarium. They are one of the most popular fish in saltwater aquariums, and for good reason. They are easy to take care of, and they are colorful, fun to watch and hardy fish. They are also very colorful and stand out from just about any other fish you are likely to have in your aquarium.

Clownfish are one of the most common types of fish found in tropical reefs. They are usually brightly colored, and are known for being very colorful and vibrant. Clownfish are very fun to watch and are not aggressive towards other fish, but will chase them away if they feel threatened. Clownfish are very easy to care for, and will only need a little maintenance.

Clownfish are well-known for being the main characters in the popular Disney movie “Finding Nemo”, and people love to buy these fish for their aquarium. They can be a great choice for a family aquarium.

Clownfish are a great option for any aquarium owner, and there are a number of reasons why.  First off, they are relatively easy to care for. When properly cared for, they can live up to 12 years. They tend to live longer in a home aquarium than in the wild.  

Another reason they are a good option is that they are very hardy when it comes to water chemistry.  They can handle a wide range of temperatures and levels of salinity. They are also not as susceptible to disease as some fish. They also live well with a wide variety of fish.

Clownfish can be purchased from a number of saltwater aquarium dealers and will cost between $20-$60.

Information on Clownfish

  • Average Length: 3 to 4 inches
  • Scale Colors: Orange, Yellow and Maroon with White Stripes and Black outlines.
  • Attention Needs: Moderate
  • Tolerance to Heat and Cold: No
  • Good Pet: Yes
  • Good with Other Clownfish: Only in pair or small groups
  • Good with Other fish species: Yes but not with other Clownfish species
  • Good for Less Experienced Pet Owners: Yes
  • Health Concerns: Clownfish Disease and Saltwater Ich
  • Average Life Span: Up to 6 years

Physical Appearance of Clownfish

a Clownfish swimming within a sea anemone

Clownfish are long-bodied fish and can grow up to 4 inches long. They have a single dorsal fin with a dip in the middle. The dip makes it look like these are 2 separate dorsal fins. They have a rounded caudal fin which somewhat resembles a two hump camel. This shorter odd shaped fin keeps them from swimming fast.

There are close to 30 varieties of Clownfish with the types False Percula and True Percula being the most common types kept as pets.

The False Percula has 11 spines on their dorsal fins while the True Percula has 10 spines. It can be difficult to see them, but if you look closely you will see them. Both the False and True Percula clownfish have orange, white and black colors on their body. There are other species of Clownfish that may be yellow or maroon colored. Years of captive breeding has resulted in several color variations of Clownfish.

A unique feature of their appearance is that they have three white stripes on their body. One in the center, one at the bottom of the caudal fin and one behind their eyes. The fins and stripes on their body are outlined in black. The outline on False Percula’s body is thinner and sometimes even absent while True Percula has thicker outlines.

Temperament of Clownfish

Clownfish are generally non aggressive and peaceful fish. They will only get aggressive if kept with other Clownfish species. It is not a good idea to keep different types of Clownfish in the same tank. It is best to keep them alone or as a mating pair in a single tank. If there is more than one male then the mating pair will get aggressive with other males.

They have a different way of swimming than other fish. Clownfish generally waddle in water. Since they are not great swimmers, Clownfish will mostly stay in higher areas in their tank that have less water current.

In the wild, Clownfish like to stay with certain species of Sea Anemone. These are predatory animals that have a flower-like appearance and are closely related to corals. The tentacles of Anemones give protection to Clownfish.

a Clownfish swimming near coral

In captivity, It is difficult to care for Sea Anemones but if you add them to your tank, your Clownfish will spend most of their time close to them. The Clownfish use the Sea Anemones for protection from other fish. The Clownfish has a thicker mucus layer than most other fish that protects them from the stings of the Sea Anemone.

Best Habitat for Clownfish

Clownfish are found in the warm waters of the Red Sea or the Pacific ocean and mostly stay by the coral reefs and their host Anemones. Anemones are a type of predatory aquatic species that eat fish, but when it comes to Clownfish they do not seem to recognize them as food.

Because they are weak swimmers, to feel safe they need a lot of hiding places inside their tank. In the wild they can live up to 10 years, but in captivity they only tend to live about 6 years. To help them stay healthy and live long, it is important to maintain ideal tank conditions.

Tank size

A single Clownfish needs a minimum tank size of 20 gallons and for each additional Clownfish, the tank size should increase by at least 10 gallons. For example, if you want to keep 4 Clownfish then the tank size should be at least 50 gallons.

If they are going to be kept with Sea Anemones then a minimum tank size of 50 gallons is needed for a single fish. The Anemones can grow up to 12 inches which can make it difficult for clownfish to swim. Having a large tank will give the fish enough space to swim. Because things get so big in saltwater tanks you can see why the tank sizes scale up so quickly.

Temperature

The temperature should be in the range of 74 to 79°F.

Water Hardness and PH

a Clownfish swimming in a bright aquarium

They need a pH level between 7.8 to 8.4 to stay healthy.

Lighting

They don’t have any specific lighting requirements but a natural day and night cycle should be maintained. Keep the lights on for 8 to 10 hours during the day and turn them off during the night. Installing a timer in your lighting system is the easiest way to set this up.

Decorations

Clownfish need a lot of hiding places inside their tank especially if you don’t have any Sea Anemones for them. You can create hiding places by adding rocks, reef inserts or live rocks. Live rocks are rocks taken from the ocean waters. These have skeletons of dead coral, bacteria, algae and invertebrates that act as biological filters for fish tanks.

Reef inserts are made from artificial material but they tend to replicate the coral found in the wild. Make sure you clean any artificial decorations thoroughly before adding them to the tank.

Tank conditions

For a Clownfish, their water needs a specific gravity between 1.020 and 1.024. Specific gravity is a term used to denote the level of relative salinity or dissolved salts in tank water when compared to pure water. Even minute fluctuations in specific gravity of your saltwater can be harmful for your fish. A hydrometer should be used to measure the specific gravity of your tank water.

Avoid keeping the tank in a location that gets direct sunlight or is close to an air vent.

Use a saltwater testing kit to regularly measure the levels of ammonia, nitrates and salinity of the water. High levels of these compounds can be harmful to your Clownfish.

several Clownfish together within the sea anemones

Tank Maintenance

A 15 percent water change should be done every week but smaller tanks might need a higher water change. In small tanks, ammonia and nitrates build up faster than in larger tanks. Testing the water quality will give you an idea of how much water should be changed.

Best Tank Mates for Clownfish

The most common tank mates for Clownfish are Anemones. 

Apart from Anemones, the recommended tank mates are:

The above mentioned fish are peaceful and easier to care for than Anemones. Avoid keeping them with bigger and aggressive fish like Angelfish, Tangs, Lionfish and Groupers or others that can eat them. Clownfish are weak swimmers and can become easy prey for more aggressive fish.

Avoid keeping more than one species of Clownfish in the same tank.

Health Issues

A healthy clownfish will have clear eyes, undamaged fins and will swim actively inside the tank. Maintaining regular water quality can help a lot to prevent your Clownfish from getting any diseases. They can still get some diseases likes:

Clownfish Disease

Brooklynella Clownfish Disease is a serious and potentially deadly disease that affects clownfish, which are popular aquarium fish. This disease is caused by the Brooklynella hostilis parasite, which can cause anemia and other symptoms in its hosts. The most common symptom of this disease is white patches or spots on the fish’s body. Other symptoms may include lethargy, loss of appetite, and cloudy eyes. In severe cases, the fish can become unresponsive and eventually die.

Symptoms of Brooklynella Clownfish Disease

Symptoms of Brooklynella Clownfish Disease include:

  • White patches or spots on their body
  • Lethargy
  • Appetite loss
  • Cloudy eyes

In more severe cases, your fish can become unresponsive and eventually die. These symptoms can appear fairly quickly after infection and can be fatal if not treated promptly with the correct medications. It’s important to monitor your fish closely for any signs of Brooklynella Clownfish Disease.

Marine or Saltwater Ich

Marine Ich, also known as White Spot Disease, is a common parasitic disease that affects saltwater fish. It’s caused by the ciliate protozoan parasite and Cryptocaryon irritans, which attach themselves to a fish’s skin and gills.

Marine Ich is very contagious and can spread quickly through an aquarium. It’s often introduced into an aquarium through new fish or contaminated equipment. Poor water quality and stress can also weaken a fish’s immune system, making them more susceptible to the disease.

Symptoms of Marine Ich

Symptoms of Marine Ich include:

  • White spots on the skin and fins of infected fish
  • Rubbing against objects in the aquarium

As the disease progresses, fish can become lethargic and lose their appetite.

Feeding Clownfish

a colorful pile of fish flakes

In comparison to other saltwater fish like Butterflyfish, Clownfish are relatively easy to feed. They are omnivores that feed on algae, crustaceans, copepods, anemone tentacles and fish eggs in their natural habitat.

Captive Clownfish should be fed a variety of food. They can be fed meat-based foods like Brine shrimp and Mysis shrimp. They can also be fed frozen fish and table shrimp. These should be finely chopped before feeding them.

Apart from meat, plant-based food like algae flakes and pellets should also be given to them.

Younger Clownfish will have to be fed in their safety area – an area with low water flow and where other fish won’t disturb them. Once they grow you can feed them in an area of your choice but even as adults they will need an area of low current to feed.

Adults should be fed twice a day while young fish should be fed 3 to 4 times a day. Give them only enough food that they can eat in about 3 minutes. Remove excess food to maintain the water quality inside the tank.

Related Questions:

Are all Clownfish Born Males?

An interesting fact about Clownfish is that all of them are born males but they can change their sex to females when they mature! Once they change their sex it cannot be reversed. The gender change usually happens when they are mating. The larger of the pair will change into a female.

Can Clownfish be Kept in a Small Group?

While it is recommended to keep them in mating pairs, in larger tanks a small group of the same species of Clownfish can be housed. Clownfish in groups follow a strict hierarchy. The largest female in the group will become the dominant leader. If the female leaves the group to stay with a male, the next male in the hierarchy will change into a female and become the leader.

Should I buy Wild-caught or Captive-bred Clownfish?

Wild-caught Clownfish can be difficult to keep in a fish tank. They are used to staying with their host Anemones and specific aquatic environments in the wild. It is not possible to replicate this in a captive environment. Wild-caught fish also have a high mortality rate of 90%. Captive-bred Clownfish, on the other hand, have been raised in a closed environment which makes them hardier than the wild-caught peers. They are also easy to care for and less costly. So it is recommended to get captive bred Clownfish.

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