Clownfish or anemonefish are an increasingly popular fish in reef aquariums.


Clownfish get their casual name from their appearance; they have an interesting orange and white pattern that could be compared to a look given by makeup. They also swim in an interesting and almost “goofy” pattern that makes them a bit clown-like.

Their proper name (anemonefish) comes from their close relationship to sea anemones.

In the Wild

Sea anemones are underwater animals that almost look more like plants than animals. They are stationary creatures with powerful defenses mechanisms that they use to eat prey who swim too close. They are similar to that of a predatory land plant, such as a Venus fly trap.

The anemone has long appendages that reach out and zap prey to incapacitate them. But the clown fish has adapted to the sea anemone and is among the few creatures who can touch it without coming to harm.

This creates a mutually beneficial relationship. The clownfish can use the anemone for protection from other fish, who cannot swim close to the anemone without being harmed. The clownfish can also eat excess food caught in the tendrils of the anemone.

In return, the waste from the clownfish provides nutrients for the anemone; which can be vital since the anemone is stuck in place and cannot go elsewhere to find these nutrients. Clownfish also feed on tiny parasites that could be harmful to the anemone.

Some people try to recreate this relationship in their aquariums.

In Reef Aquariums

Clownfish are saltwater fish and will need a tank that can accommodate them. Saltwater tanks tend to be harder to care for when compared to fresh water tanks so those looking to purchase clownfish should know what they are getting into.

Saltwater fish need plenty of room in order to be healthy. Clownfish will often need at least a thirty gallon tank. Luckily, this is not nearly as large of a tank as some other saltwater fish require by comparison.

In general, clownfish tend to be one of the better saltwater fish to have as pets due to their durability and how easy they are to take care of.

Things can become a bit more complicated for reefers who want to own sea anemones to keep with their clownfish. Sea anemones are not as common as pets although they are becoming more popular due in part to the increasing popularity of clownfish in aquariums.

An issue to keep in mind when considering a sea anemone as a pet is that they are predatory by nature and will harm or kill other fish in the tank if you own anything besides clownfish.

In Popular Culture

Those who have never seen a real clownfish before will probably recognize them from the famous Disney Pixar movie “Finding Nemo.”

Due to the popularity of this film and its sequel, more people have been taking an interest in clownfish and are seeking them as pets. They are particularly popular among families with children. They are happy to have their own “Nemo” in their fish aquarium.