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Can Fish Have Seizures And How To Prevent Them!

With more and more beginners trying their hand at fish keeping, we have seen a spike in the number of people reaching out with various questions that are often overlooked by more experienced fish keepers who are used to being in situations that are brand new to beginners.

One of these very common situations is when your fish has a seizure and more experienced fish keepers tend to be used to this but it can be brand new to beginners.

Judging by the number of people that we see reaching out and asking can fish have seizures each month, it would seem that a large number of people out there are not even aware that this is a possibility.

On top of that, it can be quite worrying the first time you see your fish have a seizure too with many of the people that we see reaching out often being worried about the condition of their fish.

Due to seeing so many people asking about fish having seizures as well as many of the people that we do see reaching out often being worried about the health of their fish, we have decided to publish this article.

Our hope is that we will be able to help as many of our readers as possible not only understand why their fish may be having seizures but also how they may be able to prevent them in the future too.

Can Fish Have Seizures?

Although rare in ideal tank conditions, fish can have seizures with the most common causes being light sensitivity, toxic shock due to water conditions, health problems, and problems in their diet.

There are a number of other potential triggers for seizures in fish too but they do tend to be very rare compared to the main four triggers.

Sensitivity in light that leads to seizures in fish is often tied to an underlying health condition with the light sensitivity and seizures being a symptom from the same cause.

Most fish will end up having a seizure if the toxicity levels in their aquarium is too high for them with more sensitive fish species being more prone to this too.

Issues with the diet of your fish is the rarest of the four most common causes of seizures in fish but it can still happen.

This could partly be down to allergies to some of the proteins used in the fish food that you are using to the fish food not being nutritionally complete for the requirements of your fish.

This is very common with people who use goldfish food for tropical fish due to the ingredients list often being very similar but the actual ratios of these ingredients used are very different to each other.

How To Reduce The Chance Of A Fish Seizure!

The easiest way to reduce the chance of a fish seizure is to keep your water conditions within recommended parameters for the fish species that you keep. It is also highly recommended that you feed your fish a suitable fish food that is nutritionally complete for their species too.

When it comes to light sensitivity and health issues being the trigger for the fish seizure things do become more complicated.

Unfortunately, the health issues that can trigger your fish to have a seizure are usually serious and untreatable with brain tumors being one of the more common ones.

Although rare, some fish can have a seizure due to receiving head trauma too but this will usually pass within a week or two provided the head trauma is not serious.

In some sensitive fish species, excessive stress and anxiety can also trigger a seizure so making sure that the aquarium that you keep your fish in is large enough for them is highly recommended too.

Signs Of Fish Having Seizures!

The most common sign of a fish having a seizure is mild twitching with this usually indicating a mild seizure. A more serious sign of fish having seizures is violent twitching followed by erratic swimming or swimming on their side followed by rapid breathing.

There is no connection between the severity of the seizure and the severity of the cause. For example, a less serious cause of a seizure in fish provided it is corrected is toxic shock and this can cause both mild and serious seizures.

On the flip side of that, a very serious cause of fish having seizures are brain tumors but something as serious as this can also cause mild and serious seizures too depending on the level of the tumor.

We just wanted to clear that up as we do see a large number of people reaching out and asking about if there is anyway way to tell the cause of the seizure by how severe it is.

Why Is My Fish Shaking?

There are a number of reasons that a fish may shake ranging from the fish having a seizure to the fish being stressed or anxious to the water conditions not being ideal. In rare situations, some fish will shake if they are having issues with parasites too.

We often see people new to fish keeping make the mistake that all fish shaking means that the fish is having a seizure but this is simply not the case.

Some fish are ultra-sensitive to their water conditions and will shake due to their water temperature of pH levels not being suitable for them.

On the flipside of this, fish species that are generally more robust to a wider range of water conditions may start to shake if their water conditions change too quickly.

Although it is common for fish to shake for a number of reasons, fish shaking due to having a seizure are definitely one of the less common causes.


That brings our article going over if fish can have seizures to an end. We hope that we have been able to clear up any questions that you had about seizures in fish as well as helped you understand that simply seeing your fish shaking in its tank does not mean that it is actually having a seizure too.