Clownfish is a popular choice for marine aquariums – in fact, it dominates 43% of the world’s marine ornamental trade.
Of all the clownfish, Ocellaris clownfish is the most sought by aquarists. This is an iconic fish with beautiful orange and white stripes, popularized by the Disney film Finding Nemo.
There’s no doubt that these magnificent creatures are a boon to your aquarium; however, many owners complain of a particular clownfish behavior. That is seeing their clownfish digging in sand, often repeatedly.
In this post, we will dig into (no pun intended) the reasons behind this strange clownfish behavior. Also, let’s see how we can stop this unwanted behavior, including choosing the best substrate for clownfish.
Let’s get started.
Why Your Clownfish Digging in Sand Is Not Good
So how can a little fun in the sand be a cause of concern for you?
Well, as it turns out, it does cause a few inconveniences.
First, your clownfish kicking up sand is bound to disperse it all over the place and make your water cloudy with sand. Although it will settle down eventually, it would interfere with the aesthetics of your aquarium.
Second, the substrate is the foundation for numerous objects within your tank – messing with the substrate can mess up your perfect arrangement of aquarium décor.
In fact, many clownfish owners reported that they lost a coral or plant because of the relentless digging by their pets.
All in all, it is not a behavior that should be tolerated.
Why Is Your Clownfish Digging in Sand?
First off, I want to say that this is a common behavior among clownfish, so it’s nothing to be alarmed about.
That being said, it is something that can get a little annoying, to say the least.
While it is a common clownfish behavior, there could be many reasons why your clownfish is doing it. Let’s look at each of them.
It Could Be a Clownfish Mating Behavior
Suspect this if you have a sexually mature pair and they are doing this mischief together. Clownfish will dig up an area when they are preparing to spawn.
Strangely, they don’t necessarily lay their eggs in the hole they dig, as they like to lay their eggs on a flat surface.
It’s more likely to be territorial display, which peaks when they are mating.
Talking about clownfish mating, there will be just one dominant female that mates with another male – other clownfish aren’t allowed to mate.
Interestingly, clownfish have the ability to change their sex from male to female. When there are no females around, one of the males will transform into the dominant female!
Clownfish mate around the full moon, so look at the calendar to figure out what they are up to.
Your Clownfish Could be Territorial
As mentioned above, it could be a territorial behavior.
So are clownfish aggressive? Well, they are one of the most aggressive fish species that you can encounter.
They are particularly aggressive towards fish that look like them; research has shown that Ocellaris clownfish look for the color and even the number of stripes on other fish to determine whether they should attack them or not.
The reasoning is simple: they don’t want to compete with their own kind for food and mates.
Some species such as maroon clownfish can be extremely aggressive in captivity.
So if you have a bunch of clownfish in your tank, one of them digging sand could be an indicator that they do not like other clownfish in their space. Aggressive clownfish will also plainly attack others that come close.
This digging behavior is more likely to happen when a clownfish establishes its territory and gets comfortable in it; in other words, this could be a sign of a happy clownfish.
They are also known to rearrange rocks and other objects as well; think of it as rearranging furniture in your living room.
Your Clownfish Wants a Hiding Spot
If you see your clownfish digging a hole and then staying in that hole, it is probably looking for a hiding spot.
A stressed fish often wants to hide itself from other fish; it could be that it is being bullied by other fish.
Remember, something out of whack with the water conditions can also stress your fish.
Your Clownfish Could Simply Be Hungry
This is a pretty straightforward explanation: your clownfish is kicking up sand to eat any leftover food that has settled to the bottom.
This is likely if you see them digging all over the place, not just in one particular area. Watch out for their immediate activity after they dig up sand: do they chase around something in the ensuing cloud of sand?
See how well your clownfish is eating during feeding time and how much leftovers they leave behind.
How to Stop Clownfish From Digging in Sand?
Many aquarists state that they struggle to control this clownfish behavior. Clownfish are notoriously adamant with this activity. No matter how many times you fill the hole in, they would dig it back up again.
The key to stopping this behavior is to find out why your clownfish is doing it and address the root cause.
There’s nothing much you can do if it is their mating behavior; even if you remove all the females, one will transform into a male.
If it is the antics of an aggressive clownfish, you can do things to mitigate it, such as getting a bigger tanker, being conservative with the stocking, and getting fish that are compatible with each other.
If your clownfish just wants a hiding spot, you can give it a few, such as plants, rocks, and caves, so that it doesn’t dig a hole in the substrate. You can even get a sea anemone, which is in fact the natural habitat of clownfish.
Lastly, if it is hunger, you can simply increase the feeding frequency to keep their bellies full.
What is the Best Substrate for Clownfish?
Marine aquariums often choose sand as the substrate to be completely immersive; it also mimics the ocean floor, so the fish will feel at home.
However, as we have seen, sand is easy to dig holes in by your clownfish.
You can get crushed coral sand instead, which is heavier than sand so it won’t get blown around easily.
If you are still insisting on sand, avoid fine sand as it can make your water really cloudy when disturbed and can even get into the filter.
Alternatively, you can get gravel – there’s nothing that says you can’t get gravel for your marine aquarium. Gravel will be harder to dig holes in, so it would basically put a stop to this annoying clownfish behavior.
Conclusion
While it is a common experience for keepers of these magnificent creatures, clownfish digging in sand can inconvenience you in many ways.
It makes the water cloudy and also disturbs your perfect arrangement of aquarium décor.
It is difficult to figure out why they do it exactly, and even more difficult to put an end to it.
Hopefully, the above information will come in handy when dealing with this issue and help you stop your clownfish from, well, clowning around.
Thanks for reading.
