Although the popularity of keeping clownfish as pets sky rocketed after the initial release of Finding Nemo, the popularity of the species within the fish keeping hobby has continued to grow over the years and they are currently one of the most commonly kept marine fish in the hobby.
Due to being such a popular option, we constantly see people reaching out and asking questions about potential problems that they are having with their pet clownfish with one of the more common questions being about their clownfish sleeping.
Contrary to what some people claim on social media, clownfish do sleep and they will usually try to sleep in an area of their aquarium tank where they feel safe.
This can range from their anemone to and area with good cover but in some aquariums with minimal cover and no anemone, the clownfish may sleep on the substrate at the bottom of their tank.
Some paired clownfish can develop a sleeping routine in community tanks where one clownfish will sleep while the other one guards it before the two clownfish switching over.
This is more common in community tanks where there are larger fish species in the same tank as clownfish though in most tanks, paired clownfish will usually not do this.
How Do You Know When A Clownfish Is Sleeping?
If your clownfish is inactive and remaining still at the bottom of its tank, near its anemone or near some other source of cover then your clownfish may be sleeping.
Clownfish do not have eyelids so they keep their eyes open when they are sleeping making it difficult to be able to easily tell if your clownfish is sleeping or not.
This can catch a surprisingly high number of people out who are new to keeping clownfish in their aquariums as they worry about potential problems with their clownfish when they are just sleeping.
Unfortunately, there is no easy way to confirm that a clownfish is sleeping or not but the majority of the time when your clownfish is staying still and inactive, it will just be sleeping.
We have seen some people on social media recommend that other fish keepers give their clownfish a little knock to try and wake it up to confirm if it is sleeping or not.
We would not recommend this unless the clownfish has been in the inactive state for over twelve hours in the same location.
Keep in mind, some clownfish will wake up as their keeper sleeps, change location, then go back to sleep before you wake. We have actually seen some people set up their smartphone to timelapse their clownfish while they sleep to make sure that their pet is ok.
Do Clownfish Sleep In An Anemone?
Most clownfish that have started to host an anemone will sleep in or on their anemone due to it offering them protection while they are sleeping.
This is a very common behavior with clownfish and some anemones are large enough for the clownfish to burry itself in the anemone to hide completely while it sleeps.
The problem with this is that a huge number of people who are new to keeping clownfish as pets in their aquariums choose unsuitable anemones for their clownfish that they will refuse to bond with.
In most cases, clownfish will bond with a suitable anemone but keep in mind that different types of clownfish will need different anemones due to the different toxins in different anemones.
If you match the two up together correctly then your clownfish will often sleep on or in its anemone rather than anywhere else in its aquarium.
Is It Normal For Clownfish To Be Sleeping On Sand Or Substrate?
Depending on your aquarium setup, it can be normal for your clownfish to sleep on the substrate in its tank be it sand or some other type of substrate.
Most clownfish will usually prefer to sleep on an anemone or some other type of cover but if this is unavailable for your clownfish then they will often sleep on the substrate in the tank.
If you are keeping a community tank then it can be common for the other fish in your aquarium to nip your clownfish while it sleeps on the substrate of our tank.
This can cause your pet clownfish to become stressed and anxious resulting in clownfish aggression towards its tank mates.
A clownfish sleeping on sand or substrate in its aquarium can sometimes make the fish more susceptible to various types of infections so it is usually better to offer some type of anemone or cover for your clownfish to sleep near.
In almost all cases, a suitable anemone should be the primary option for a clownfish to sleep on but even then, a small number of clownfish that have started hosting an anemone may still choose to sleep somewhere else.
Do Clownfish Sleep On Their Side?
Clownfish do not always sleep on their side and they will move around with the water flow as they sleep making it look like they are changing their sleeping position.
Even if your aquarium has minimal water flow levels your clownfish will usually still change its sleeping position naturally rather than just constantly sleeping on its side.
If you keep multiple clownfish in your aquarium and they are constantly fighting each other in a bid to establish a hierarchy then injury may cause some clownfish to sleep on their side more often than they should.
There are also a number of potential problems that can also cause your clownfish to have problems sleeping naturally like swim bladder disease too.
That brings our article going over the various clownfish sleeping habits to an end. We hope that we have been able to help as many of our readers as possible better understand the various behaviors that their clownfish may display when sleeping. The majority of the things that a clownfish will do when they sleep are totally natural and normal but due to a lack of eyelids on clownfish, even experienced fish keepers can worry about their pets when they are not sure if they are sleeping or potentially having a problem.