Why Do Goldfish Chase Each Other? (9 Cool Facts)

Goldfish are usually calm. But there are times when you may find them chasing each other. This may cause you concern, as you try to figure out whether it is an indication of something that is wrong with them. Read on, to find out why goldfish sometimes chase each other.

Why do goldfish chase each other? Goldfish may chase each other as part of mating behavior. Overcrowding, competition for food, territorial behavior and stress can also make them chase each other. Sometimes though, when goldfish chase each other, they are just playing.

Do Goldfish Recognize Each Other?

Before venturing to answer the why do goldfish chase each other question at length, we need to first pause, and find out whether these fish actually recognize each other.

The truth of the matter is that goldfish do recognize each other. It is worth knowing that these fish have large eyes, through which they are able to see and recognize their tank mates.

Moreover, these fish have good hearing and a keen sense of smell. These senses also help them in recognizing each other. The sense of smell, for instance, helps them to recognize each other’s pheromones.

This understanding – that goldfish recognize each other – will be helpful when we get into answering the why do goldfish chase each other question at length.

Why Do Goldfish Chase Each Other?

Often, when goldfish chase each other, it is for mating purposes. If you have males and females, and the breeding season comes, you can be sure that there will be a lot of chasing around.

During these mating rituals, it is always the males that chase the females. The males do so with the aim of bumping the females’ bellies, which would cause the females to release the eggs therein.

Once the females release the eggs therein, the males can proceed to fertilize them. So this is what goldfish mating entails, in a nutshell.

Another reason that may make goldfish chase each other is competition for space and food.

If you keep your goldfish in too small a space, they may keep on chasing each other. And if you don’t give them enough food, they may chase each other as part of food competition/in search of food dominance.

Should you introduce a new goldfish into an aquarium or pond where others were living for long, they may start chasing the new fish. This would be as part of territorial behavior.

If a goldfish is sick or injured, its tank mates won’t try to empathize with it. They will instead chase it, and try to bite it. So if you have a sick or injured goldfish, you may see others chasing it around, and generally trying to get rid of it.

Stress too can make goldfish chase each other. This may be stress from having too little space, having too little food, being in a space that is too polluted and so on.

Sometimes, mixing goldfish breeds may cause chasing. For instance, common goldfish have a tendency to chase fancy goldfish.

Of course, there are also cases where the goldfish that are chasing each other are just playing.

Do Goldfish Play With Each Other?

While answering the why do goldfish chase each other question, we often have to digress into a discussion on whether goldfish play with each other.

This is because, according to many schools of thought, one of the reasons why these fish chase each other is playing. So people want to know whether, indeed, goldfish are capable of playing with each other.

As it turns out, goldfish do play with each other. It is worth remembering that these are among the types of fish that are considered to be ‘social’. And one way in which they savor each other’s company is by chasing each other.

This sort of chasing is actually part of happy goldfish behavior.

Therefore if you have been wondering, why does my goldfish chase each other, then you need to know that it could be that they are just playing.

Playful chasing is not one sided though. In playful chasing, you have the fish that are involved mutually giving chase. So it is not a case of one fish continually chasing and seeming to harass another one.

Sometimes, the playful chasing may be in circles. Therefore if you have been wondering why are my fish chasing each other in circles, one possibility may be that they are playing.

Is It Normal For Fish To Chase Each Other?

Often, the people who pose the why do goldfish chase each other question want to know whether the chasing behavior is normal.

There are instances where the chasing behavior is normal. And there are instances where the chasing behavior is abnormal.

Where, for instance, it is part of mating or playing, the chasing is normal.

But where it is because of being in too small a space, or due to competition for food or due to bullying, then it is not normal.

Admittedly, it can be hard to differentiate the normal chasing from the abnormal chasing. For instance, we often come across this question: are my goldfish fighting or mating?

As a general rule, the normal chasing is that which doesn’t cause major injuries, especially to the tails and fins.

On the other hand, abnormal chasing tends to be aggressive, often leading to injuries, especially to the tails and fins.

In this context, abnormal chasing may be where a common goldfish is chasing and seemingly trying to injure a fancy goldfish. Or it may be where one goldfish is trying to bully another. It may also be where one fish is trying to gobble all food, to the exclusion of all others…

The only ‘normal’ type of chasing that may be somewhat aggressive is that which is associated with mating. In it, there may be a bit of trying to bite the female’s tail and fins – though the real aim is always to bump the female’s belly, in order to release the eggs therein.

Why Do Goldfish Chase Each Other In A Tank?

If you keep your goldfish in a tank, there are times when you may find them chasing each other. This leads to the question on why do goldfish chase each other around the tank?

Sometimes, you find that the reason is that the tank is too small. So the fish are essentially fighting for space.

At other times, it may be that the fish are not getting enough food in the tank. So they chase each other as part of food competition.

If you have a relatively dull goldfish in the same tank with a relatively brighter colored goldfish in one tank, the former may keep on chasing the latter.

That, for instance, is what you may get if you have a fancy goldfish in the same tank with a common goldfish.

Of course, the goldfish chasing each other in a tank may be just playing.

Or the goldfish chasing each other in a tank may be mating. So in this case, you have the male chasing the female around, in a bid to get her to release her eggs, which he can then proceed to fertilize.

Why Do Goldfish Chase Each Other In A Pond?

If you keep your goldfish in a pond, you may at times find them chasing each other. This then leads to the question: why do goldfish chase each other around the pond? Or, in other words, why do my pond goldfish chase each other?

A pond is usually much bigger than an aquarium/tank. Therefore overcrowding may not be one of the reasons for goldfish chasing each other in a pond.

Further, if it is a natural pond, there may be plenty of natural food for the fish in the pond. Therefore lack of food may also not be the reason for the fish chasing each other in a pond.

The question then becomes, why do goldfish chase each other in a pond – in spite of there not being space and food constraints?

One reason may be that the goldfish are trying to establish dominance over each other.

Another possibility may be that the goldfish are simply playing.

Yet another possibility may be that the goldfish are mating. As we all know, mating in these fish entails a lot of chasing. The male is not chasing the female to mount her. On the contrary, the male is chasing the female to get her to release eggs, which he can then fertilize.

What Does It Mean When Goldfish Chase Each Other?

This is another way of framing the why do goldfish chase each other question. So, indeed, what does it mean when one fish chases another? Why do goldfish chase each other around?

One common reason for goldfish chasing each other around is mating. If it is during the mating season (during which the males acquire breeding stars), and it is the males chasing the females, then this is the most likely reason.

Goldfish can also chase each other as part of play.

If goldfish are under stress, they may also start chasing each other. This may be stress that arises as a result of being in too small a pond or having too little food.

It may also be a case where some goldfish chase others as a way of bullying.

If you have your goldfish chasing each other, it may be an indication that you have mixed goldfish types that ideally shouldn’t be tank mates. For instance, if you put a goldfish that has a bright fin/tail with one that doesn’t, the latter may keep on chasing the former.

So if you have a fancy goldfish living with a common goldfish, the result may be endless chasing. This will be because the common goldfish is continually fascinated by the bright tail/fins on the fancy goldfish.

The chasing may also mean that the fish are being territorial. For instance, if you introduce a new one into a tank where others have been living for long, the old fish may behave in a territorial manner – by chasing the new one around.

At another level, the chasing may also mean that there are sick or injured goldfish in the tank/pond. So the others try to get rid of it by chasing it – lest it becomes a ‘liability’ to them.

Can Goldfish Kill Each Other?

It is rare for goldfish to kill each other. But they do sometimes hurt each other badly. Chasing in these fish often entails nipping on one another’s tail and fins. This can cause nasty injuries at times.

But it is worth mentioning that goldfish have a tendency to chase (and nip at) injured or sick tank mates. So you have a fish that is already sick or injured. Then its mates go ahead and chase it, after which they nip at its tail and fins. This can very well eventually kill the fish.

How Do I Stop My Goldfish From Chasing Each Other?

This question on how to stop my goldfish chasing each other is a natural extension to the one on why do goldfish chase each other?

After finding out why they chase each other, one naturally wants to know, how do I stop my fish from chasing each other. You have to start by finding out why exactly the fish are chasing each other.

Is it because of overcrowding/being in too small a space? Then get more space. Have at least 10 gallons of water per fish.

If it is because of food competition, provide them with adequate food. Also ensure that you spread the food around, instead of pouring it into one part of the tank/pond which often leads to a frenzy.

Where it is because of bullying, you may need to first identify the bully. Then use a tank divider to separate the bully from the fish he is bullying. Or simply transfer the bully to another tank/pond.

Where the chasing is due to play, there may not be much you can do it. Just ensure that it doesn’t escalate to bullying.

And where it is due to mating, again, there may not be much you can do. Just ensure that there are not too many males competing for too few females, which can overwhelm both the males and the females.

As a general rule of the thumb, you can have one male for every three females, to avoid overwhelm.

Final Verdict – Why Do Goldfish Chase Each Other

Goldfish may chase each other as part of their mating behavior. They may also chase each other because of the stress that comes from overcrowding or lack of adequate food.

There can also be cases of these fish chasing each other as part of bullying or in a bid to assert dominance.

But the chasing can also be playful, which is part of happy goldfish behavior.

To ensure that you don’t have too much chasing, provide the goldfish with adequate space and food. And ensure that you don’t have too many males competing over too few females.

As a pet lover, make sure to learn about pet more and give your pet fish a good and comfortable life!

Rajkumar Ravichandran

Welcome to Learn About Pet. My name is Rajkumar Ravichandran and I love all pets, travel, and amazing food. I write about my passion and personal experience caring for multiple pets in this blog! ❤️