Skip to Content

Should You Keep Crayfish With Goldfish?

Goldfish are the most common freshwater fish in the world by far with fish keepers of all levels of experience often having at least one species of goldfish in their collection of fish in one tank.

Due to their huge popularity with fish keepers all over the world, we often see people asking for advice on keeping pet goldfish, especially potential tank mates and the rising popularity of pet crayfish has resulted in people asking about keeping crayfish with goldfish.

You should not keep a crayfish in the same tank as goldfish as even a small crayfish is often able to catch a goldfish in its claws and eat it.

Some goldfish species are particularly docile, especially after eating making it considerably easier for a crayfish to grab the goldfish and eat it with many people often overlooking just how much of a risk this is to your fish.

After publishing our article going over if crayfish will eat the snails in your tank, we realized that many people new to the fish keeping hobby are drastically unaware of just how aggressive crayfish, especially hungry crayfish can be and that they also put your fish at risk too.

This is why we wanted to publish this article to try and help as many of our readers as possible who are thinking of adding a crayfish to their aquarium tank.

Will A Crayfish Kill My Goldfish?

It doesn’t matter what species of crayfish you keep in your tank with your goldfish, there is always going to be a high chance of your crayfish killing and eating your goldfish.

The odds of this happening start to increase with smaller tanks where the fish have less space to stay away from the crayfish as well as if you keep the more docile species of goldfish.

This is why we would always recommend against keeping a crayfish in any sized aquarium with goldfish.

Even if you have a larger aquarium with plenty of space for your goldfish to avoid your crayfish, there will always be a risk of them becoming your crayfish’ next meal.

Many of the people who do have their heart set on keeping a pet crayfish will simply set up a suitable crayfish aquarium tank away from your goldfish.

In some cases, your crayfish may not even be able to lock a secure grip on your goldfish to actually kill and eat it with your goldfish being able to get away.

Unfortunately though, this will often result in the goldfish being maimed and seriously injured and often dying at a later date and ending up as food for your crayfish anyway.

Are There Any Herbivorous Crayfish?

All crayfish species are omnivores that will often try to get protein sources as a food source if possible and eat plant based food as a secondary food source.

In some situations, crayfish can become facultative herbivores meaning that they will only eat plant based foods if that is all that is available to them but they will still try to get meat based foods if possible.

Some species of crayfish can end up becoming increasingly aggressive when on a strict plant based diet too encouraging them to try and attack the fish in their tanks.

As we mentioned above, the odds of a crayfish catching a goldfish are pretty high to start with but with the increased aggression from a crayfish deprived of protein only increases this as the crayfish will attempt to catch the goldfish more often.

If you have a planted tank with your goldfish and crayfish in it then you will often see your crayfish trying to hide in the plant cover to further increase the odds of it being able to catch and eat a goldfish.

Then you have to factor in the fact that many goldfish species are not alert or intelligent and actually become quite docile after being fed further increasing the chance of your crayfish catching and eating a goldfish.

Should You Keep Crayfish With Goldfish?

We would never recommend that you keep a crayfish in the same tank as a goldfish as the chances of the crayfish being able to catch and eat your goldfish or seriously hurt them when trying to catch them are simply too high.

There are plenty of crayfish tank setups without fish in them that work well and should be used instead while also often working in smaller tanks helping to keep your costs low.

One thing that many people who keep multiple aquarium tanks with one dedicated to crayfish do is use their crayfish as a dead fish disposal system.

They essentially feed their crayfish a commercial diet and then when one of their fish from their tanks die, they have a crayfish waiting to eat it and dispose of the fish while keeping the crayfish’s diet as close to what it would eat in the wild as possible.


That brings our article going over keeping crayfish with goldfish and we hope that we have been able to help you better understand the potential risks to your goldfish with this type of tank setup. It is very common for people to keep goldfish and more and more people within the fish keeping hobby are also looking to start keeping crayfish too but separate tanks should always be used.