Crayfish are freshwater crustaceans that look like miniature lobsters, often leading to them being misidentified. Although their natural habitat is in streams and rivers, crayfish can easily be kept as pets in an aquarium.

Electric blue crayfish often make beautiful pets and are incredibly popular for aquariums. If you’re interested in filling your aquarium with crayfish you might be wondering: What do crayfish eat?

In this article, I cover some key information about crayfish and their diet, so you can gain a better understanding of this fascinating crustacean before you think about adding them to your aquarium.

What do crayfish eat in the wild?

In the wild, crayfish tend to live in freshwater streams and rivers, so their natural environment is often surrounded by rocks, mud, vegetation, and a fast-flowing current.

Crayfish will typically eat whatever they can catch. As scavengers, they’re not particularly fussy!


Since they are slow-moving crustaceans, they are rarely able to catch and eat the majority of live fish or shrimp that reside in the rivers and streams that they occupy.

That being said, their diet primarily consists of decomposing animal matter and decaying vegetation that rots in the water.

These are the easiest food sources that a crayfish can eat as they are no longer too quick for the crayfish and can be ripped apart by their claws with ease.

Crayfish are nocturnal and tend to live under rocks, emerging at night to feed on any food source they can find. Although the large bulk of a crayfish’s diet is aquatic plants and insects, they will eat fish, shrimp, worms, snails, water plants, and plankton.

That being said, crayfish also eat small live fish if they swim close enough and some species will readily hunt live prey more than others.

This is why they often have to resort to eating rotting fish and vegetation in the wild, as it is often all that they are capable of catching!

They primarily use their claws and first two pairs of walking legs with small pincers on the end to pick up their food and eat it.

That being said, because crayfish are nocturnal, they often struggle to search for food and thus, have to resort to scavenging for whatever they can find.

What do crayfish eat in an aquarium?

Before adding crayfish to an aquarium, you need to make their tank as similar as possible to their natural habitat.

While crayfish aren’t particularly demanding pets in terms of what they eat, if they are placed into a foreign environment, they can be reluctant to eat if they become too stressed.

To replicate their natural habitat, then, you will need to fill the tank with plenty of rocks and a layer of aquarium gravel for them to burrow into.

Crayfish thrive in cool conditions such as mudflats and riverbeds, so you will need to ensure that you don’t get a heated aquarium.

You will also need to search for tanks that feature built-in aeration and filtration units to keep the water clean and to ensure that it is circulating properly.

It is also important to note that you will need to change the water in the tank once a week at a minimum. Crayfish tend to produce large amounts of waste products that can be taxing on standard aquarium filtration systems.

Sinking shrimp pellets or lobster bites should make up the majority of your crayfish’s diet. Pellets are high in protein and contain all the nutrients crayfish need to grow and develop healthy shells.

That being said, you should also supplement your crayfish’s diet with a variety of vegetables. Crayfish will eat a variety of vegetables, including zucchini, carrots, cabbage, and spinach.

If you have any leftover vegetables from your own dinner, you can drop them into their tank as well. This will give them something different to eat and will help you minimize your own food waste!

You should try to introduce a variety of food into their diet, as a combination of meaty foods and pellets ensures a healthy, balanced diet and good nutrition for your crayfish.

It also keeps things interesting for them, as they would never be eating the same meal everyday in the wild. It is important to mention that you will need to be careful to not overfeed your crayfish.

One or two shakes of shrimp pellets or a few pieces of vegetables per day should be more than enough to keep your crayfish satiated. 

Additionally, you will need to make sure that you remove any uneaten portions of food soon after you feed your crayfish. Any leftovers that are left at the bottom of the tank will quickly decompose, dirtying the water, and will require you to change the water more frequently.

As it is already recommended that you change their water once a week, you won’t want to increase the amount you need to change it!

In Summary 

Crayfish aren’t fussy when it comes to what they eat. From fish to shrimp to all sorts of vegetation, the list of foods that they like to eat is wide.

Their diet in the wild will differ slightly from their diet in an aquarium, so make sure that you do your research before feeding your crayfish a new food.

You will also need to make sure that you are cleaning your crayfish’s tank regularly so that they are able to thrive in their environment.