Clownfish are one of, if not the most popular marine fish for people to keep in their saltwater tanks with many people new to fish keeping opting to go with clownfish due to the popularity of the Finding Nemo movie.
Clownfish do tend to be very beginner-friendly and will often make an excellent entry-level fish and cause you minimal problems in your tank provided you are able to maintain their required water parameters.
That said, we do constantly see people reaching out and asking questions about their pet clownfish shaking such as why is their clownfish shaking or how do they stop their clownfish shaking.
There are a number of common reasons that a clownfish may randomly shake in its tank with some of these causes being relatively common so it is easy to see why so many people reach out about their pet clownfish shaking each month.
We have decided to publish this article going over the more common causes of shaking in clownfish in the hope that we will be able to help our readers better identify any potential causes of the shaking in their clownfish quickly.
Depending on the suspected cause of the shaking, you may have to take steps to correct the problems in the tank but sometimes, the clownfish will be fine if you just leave it to do its thing.
The Clownfish Mating Dance!
The most common reason that a clownfish will twitch in its tank is due to the clownfish mating dance and this is totally normal for tanks with multiple clownfish where a dominant female is present.
The male clownfish in the tank will “twitch” as a part of their mating dance to try and impress the female clownfish and there is usually nothing wrong with the clownfish.
Depending on the specified species of clownfish that you keep in your tank, the male or female clownfish may also chase and nip the other clownfish during the mating dance with this usually being normal too.
A female clownfish is usually much larger than a male clownfish helping you identify if you have a female clownfish in your aquarium as some people new to fish keeping are unable to identify male and female clownfish.
If all of the clownfish are around the same size then it is more likely that your clownfish are simply fighting each other to become the dominant male in the tank.
We will cover this in more detail later in the article though as it really needs its own specific section and is not as common as the mating dance as a cause of twitching in clownfish.

An Unsuitable Anemone!
Many clownfish owners like the idea of their pet clownfish hosting an anemone so they add a pretty looking anemone to their tank and presume that clownfish can host any anemone but this is far from correct.
Many anemone can still sting your clownfish and this can cause them to twitch if the anemone sting is strong or the clownfish is young.
As we covered in our article on how to treat black spots on clownfish, the majority of clownfish will be fine if they do end up getting stung by an anemone as the majority of anemones that people get are not fatal to clownfish, especially with a single sting.
Our article on the best anemone for clownfish can help you avoid these issues though and still get a pretty looking anemone in your tank for your clownfish to host that will not cause it to randomly shake due to being stung.
If you do suspect that your clownfish is twitching randomly due to having an unsuitable anemone in its tank that it stinging it or you simply want to avoid this risk all together then a fake anemone may be the best option to take.
As we explained in our article on using a fake anemone for clownfish, you can avoid the sting risk to your clownfish by using a fake anemone with many clownfish still pairing with the anemone without issue.
Your Clownfish Is Being Bullied!
Many people fail to realise just how aggressive clownfish can actually be to each other due to thinking that they are cute and cuddle after watching the Finding Nemo movie.
Most clownfish species can be very aggressive when establishing dominance in the tank and weaker clownfish can often be bullied by the stronger clownfish until a hierarchy is formed.
This may end up in the weaker clownfish having higher stress and anxiety levels and them randomly shaking and twitching.
We have an article going over how to deal with aggressive clownfish but for many people new to fish keeping, it can be problematic as they often have a single tank so are not able to separate their clownfish who are fighting.
If you do only have a single tank then your best bet is to hope that one of the clownfish will submit to the other as the fighting will often stop once the hierarchy has been formed within the tank.
The dominant male will then transform into a female and the male clownfish will start shaking and twitching as a part of their mating dance rather than due to heightened stress and anxiety levels.
Potential Issues With Bacteria Or Parasites!
A rare cause of shaking and twitching in clownfish is problems with bacterial or parasites either on or in the clownfish causing it to randomly twitch and shake.
If this is the case then it is usually easy to identify as the texture and color of its scales can change for external infections and its poop will often change color for internal infections.
The majority of problems with bacterial or parasitic infections that can take hold of your clownfish are relatively easy to treat thankfully.
You are often able to use Melafix for the infection but keep in mind that it is not a reef safe treatment and may cause issues with corals or sensitive anemone in your tank.
If you do have sensitive anemone or corals in your tank that Melafix may harm then you can try to quarantine your clownfish into a separate tank for temporary treatment with Melafix.
The majority of bacterial and parasitic infections will usually be treat within a week so it’s often not a problem for your clownfish.
Problems With Water Parameters!
There are a range of potential issues with water parameters that can cause a clownfish to shake or twitch depending on the situation.
You really do need a suitable water test kit to narrow down the potential issues with water parameters in your tank though due to the number of things that can be out of balance being spread over a wide range.
The best thing is about issues with water parameters is that once you have workout what is out of range for what your clownfish requires, it is usually very easy and straight forward to fix with minimal effort being required on your part.
The majority of clownfish species will return to normal within a day or two of having their water parameters corrected too.
Just keep in mind that many people discount this as a potential cause when people reach out due to presuming that people new to fish keep monitoring their water parameters as closely as more experienced fish keepers.
This is far from the case and we often see people brand new to fish keeping having issues within months due to never checking their water parameters.
Conclusion
That brings our article going over why your clownfish may be shaking to an end. We hope that we have been able to help you identify the reason that your pet clownfish is shaking as well as how you are able to correct the issue. Although many people do get worried about their clownfish shaking, it is often very easy to fix and there should be no long term problems with your pet clownfish that will cause it harm once the cause of the shaking or twitching is corrected.