What Do Crayfish Eat?

Crayfish, also known as crawfish, crawdaddies, crawdads, freshwater lobsters, mountain lobsters, mudbugs, etc. are freshwater invertebrates. In recent years, they have also become quite popular in the fishkeeping hobby due to their unique personality, form, and stunning colors.

Crayfish are quite attractive, lively, and fun to watch as they scavenge for food in display tanks. They feed on detritus, animals, and plants, either living or decomposing. Also, their low demands and easy care make them excellent candidates for freshwater aquaria.

What do crayfish eat specifically? This is one of the most common questions that bother fishkeepers and enthusiasts, as most people are eager to find out what these amazing crustaceans eat in the wild and in aquariums.

In this article, I will highlight the various food sources available to crayfish for consumption in their home, and how often they should be fed in captivity.

What Do Crayfish Eat In The Wild?

Before we jump into the discussion of crayfish feeding preferences in aquariums, I need to start off with a general description of what they eat in nature. This information will help us to better understand their feeding requirements.

Crayfish inhabit freshwater streams, rivers, and swamps where they actively explore muddy bottoms due to their inability to swim to the water surface. The lower levels of these habitats are characterized by the presence of a soft or muddy substrate, ample rocks, green plants, and fast water currents.

There’s no denying that living in such a rich environment would most likely grant them access to various food sources.

Decaying Matter

Crayfish are omnivores, feed on decaying matter, and that can be said to be their primary diet in the wild. These consist of decomposing animals and decaying plants which are easy to shred with their large, sharp claws.

Green Matter

Apart from the consumption of decaying plant and animal matter, these crustaceans will source for other food items accessible within their habitat. Of course, they seem to appreciate the green matter, so they will feast on live plants, algae, biofilm attached to rocks and twigs, as well as detritus lying on the substrate.

Animal Matter

Since Crayfish are not strong swimmers, these critters can only seek out and consume food that sinks to the bottom of the waters they live in.

These animals are most active at night, thus they will scout for smaller-sized animals such as:

• insect larvae,
• worms,
• tadpoles,
• small frogs,
• snails,
• dwarf shrimp,
• small fish are not left out.

Surprisingly, these decapods may engage in cannibalism of conspecifics to survive when overcrowded and/or other food sources are unavailable.

Basically, crayfish won’t hesitate to grasp the prey with their strong claws if it is within their reach. As we can see, crayfish will eat almost anything they come across.

However, does it mean that we can give them whatever we like or that we should not care about their diet?

No, it does not!

Some food can be more beneficial than others. So, if we know the specific nutritional requirements of the crayfish species we keep and the peak period of nutrient intake, we will be equipped to plan for their feeding for optimal nutritional benefits, which will result in a happy pet. 

What Do Crayfish Eat In The Aquarium?

Having discussed what crayfish eat in their native environment, let’s look at what they eat in the aquarium.

First, before you go about considering likely food options for your pet crayfish, it’s appropriate to establish a healthy and optimal environment that closely replicates the conditions of their natural habitat.

However, when you start creating their new home, you should also understand some limitations because it may be directly correlated with their feeding preferences.

Plants

In the wild, many crayfish species are found in dense vegetation. However, if you decide to put your crayfish in planted tanks, it will be a huge mistake!

As I have already mentioned earlier, many crayfish species will eat, cut, and uproot any plant in the tank. In the aquarium, crayfish become lawnmowers.

Most crayfish species and planted tanks are not compatible (except, dwarf crayfish species like Brazos Dwarf Crayfish, Dwarf Mexican crayfish, Cambarellus Diminutus). So, do your research beforehand!

Plants are a delicacy to crayfish; they will often eat and cause damage to the plants due to their destructive nature. That’s why experienced aquarists who own planted aquariums tend to shy away from crayfish.

Therefore, unless you are ready to buy some cheap plants you are willing to lose, it will be better to focus on floating plants or fake plants.

Floating plants will be a good choice for crayfish tanks. They simply will not be able to get them, so you should have a problem.

Manufactured Foods

There are diverse food sources for crayfish, and it is vital to offer them a varied diet that is composed of animal and plant matter to ensure they get all the nutrients (protein, fiber, vitamins, and minerals) needed to thrive.

Ideal food sources include the popular Dry pellet foods and Frozen foods. These are commercially prepared, high-quality foods that contain high amounts of protein & vitamins and sink down to the bottom of the aquarium.

In this regard, sinking shrimp pellets and fish foods are very much acceptable by crayfish.

Good examples of these are (links to check the price on Amazon):

• API Fish Food flakes,
• Dennerle Shrimp King Cambarellus,
• Tetra ShrimpWafers,
• Frozen blood worms,
• Shrimp pellets
• Shrimp Granules
• Hikari Shrimp Cuisine, 
• Hikari Tropical Crab Cuisine.

Live Foods

You can also serve small live foods like shrimp, snails, grindal worms, detritus worms, and feeder fish, these are good food options for crayfish since they like to utilize their instincts to capture live prey.

Note: Crayfish are not adapted for efficient hunting. Therefore, live food should be considered only as supplement feeding.

Related articles:

• Crayfish and Suitable Tank Mates
• Can You Keep Crayfish With Other Fish?

What about vegetables?

Those are ideal too and rich in vitamins, crayfish love vegetables like cabbage, lettuce, spinach, carrot as well as shelled peas and small bits of fruits.

Additionally, since these inverts like to eat decaying vegetation, you can serve them your leftover veggies that are about to go bad and they will gobble it down in no distant time.

Some crayfish species seem to have an appetite for algae. So it shouldn’t be surprising to occasionally see them having a go at algae growing on rocks and wood in your tank. They will also make a meal out of the shoots of your live plants.

You can read my article “How to Blanch Cucumbers and Zucchini for Shrimp, Snails, and Fish the Right Way.”

List of Suggested Foods

The following are suitable food items for your pet crayfish:

• Algae wafers
• Brine shrimp
• Blackworms & Bloodworms
• Calcium supplements (cuttlebone, eggshells)
• Dead fish & shrimp
• Fish foods
• Frozen foods (frozen bloodworms, freeze-dried krill, etc.)
• Fruit
• Insects
• Krill (freeze-dried)
• Live plants
• Live shrimp and snails
• Meat (dead fish, shrimp, etc.)
• Mosquito larvae
• Shrimp pellets
• Spirulina
• Vegetables

Calcium Supplement

Crayfish must molt or shed their hard exoskeleton to increase in size. After molting (read more about this process here), the metabolic demand (to harden the shell) for calcium is particularly great. Crayfish use calcium to produce a new and healthy shell.

Supplement their diet and make sure they get enough calcium (for the exoskeleton) by regularly feeding specialized invert foods. For example,

Mineral Stones and Cuttlefish bones – links to check the price on Amazon.

I highly recommend reading my article “How to Supplement Shrimp and Snails with Calcium”.

How Often and How Much Should You Feed Crayfish?

These inverts do not need to be fed large amounts of food to thrive. Offer your adult pet crayfish food in small bits or pieces every day or two to prevent it from starving and picking on tankmates.

However, young crayfish, we should feed them every day. They need a lot of food to grow and molt.

In most cases, juveniles or young crayfish will eat the same meals as adult crayfish, to foster development; be sure to feed them every single day without skips. With juveniles, you can give them more, just do not forget to remove all leftovers.

According to some crayfish farms’ recommendations, the amount of food required for each individual is up to 5% of its weight.

Well, in home conditions, the optimal dose is usually determined empirically. When you target feed, ensure that the pieces of food served are no more than 1/2 of the crayfish carapace. This should be the ideal size for all protein-rich food items you plan to feed the crayfish, whether meat cubes, shrimp, etc.

Tip: If you see that crayfish do not come to the food as fast as it used to, it simply means that it is not very hungry. Therefore, you can change your schedule to 3 times a week.

Crayfish do not eat fast. So, you can leave their food in the tank for 10-12 hours before removing it.

Just make sure that whatever they do not consume in one day is removed to prevent fouling the water.

The most important thing is that you need to understand what works for you and the crayfish. You need to find the balance. That is why be ready to change the routine when it is necessary.

Food Variations

Some aquarists stick to one food product and give it all the time.

This is wrong. Please, do not do that.

Considering their lifespan, imagine yourself eating the same food for years!

Ideally, you need to have at least 2-3 different types of products to vary. It will give your crayfish more vitamins to improve their immune system and prevent molting problems.

Optimal Feeding Time

Although some individuals do not mind be active even in the daytime, generally, crayfish are nocturnal animals. Their feeding activity increases at night (a few hours after the onset of darkness).

So, keep in mind that they may ignore the food till it’s night-time when they are more active.

For best results, give them food before nightfall. It will replicate the conditions and environment under which they eat naturally.

Overfeeding and Underfeeding

DO NOT think that overfeeding your crayfish is not a big deal. 

• Uneaten food can quickly decompose and cause an outbreak of infections and parasites. If you are overfeeding your crayfish there is a very high chance that Planaria, Hydra, and other unwelcomed parasites will visit your tank one day.
• It can crash your nitrogen cycle. Ammonia and nitrates are caused mostly by an excess of food and organic waste. Therefore, you need to check how much you are feeding the crayfish.

Be consistent and don’t overfeed them. This is a universal rule and it concerns all crayfish species.

I cannot even stress enough how important this rule is. Unfortunately, a lot of beginner crayfish keepers usually forget about it or believe that it is not a big deal to give their pets a little bit more.

That is why I have to repeat – remove uneaten food at least after 24 hours to prevent it from dissolving and ruining the water quality. If your pet crayfish is not eating the food provided at a given time, try switching it to another food item, and observe its reaction. When they still don’t want to eat, check the water parameters to be sure that the values are right.

At the same time, these crustaceans will exhibit their cannibalistic side when they don’t get enough food to eat, so make sure to maintain regular feeding schedules. They may even emerge from their hideouts at specific periods to eat, this is behavior they tend to adopt over time if the fishkeeper sticks to a particular feeding time every day.

Crayfish Species Diet Preferences 

Procarambus Clarkii

Procambarus clarkii is a generalist omnivore species. In their natural habitat, crayfish feed on plants, algae, dead and live animals such as insects, annelids, nematodes, platyhelminthes, tadpoles, fingerlings, small fish, snails, etc.

Interestingly, pre-adult and adult Procambarus clarkii tend to be more herbivorous, whereas juveniles tended to be more predatory and carnivorous. The main reason behind this is that at this stage, juveniles require a lot of protein and in the absence of food can even start cannibalizing fast.

Diet	Omnivore / Herbivores (as adults) Omnivore / Carnivore (as juveniles)
Plant Safe	No
Temperament	Very aggressive

For more information, read “Procambarus clarkii – Detailed Guide: Care, Diet, and Breeding”.

Blue Crayfish (Procambarus Alleni)

Blue Crayfish are omnivorous and opportunistic feeders. They will eat just about anything they can get their claws on in your tank.

Live plants, blanched vegetables, sinking pellets, wafers, dead and dying fish, shrimp, snails, etc. – everything is on the menu.

Diet	Omnivore / Herbivores (as adults) Omnivore / Carnivore (as juveniles)
Plant Safe	No
Temperament	Very aggressive

For more information, read “Blue Crayfish – Detailed Guide: Care, Diet, and Breeding”.

Yabby (Cherax destructor)

Cherax destructor is an opportunistic and omnivorous feeder. They will act as a scavenger in the aquarium, eating any food that comes to rest on the bottom.

According to different studies, plant material and detritus often dominate the gut contents. However, Cherax destructor species have the ability to switch food preferences.

For example, when high protein food sources (fish, snails, etc.) become limited they easily switch to a predominantly herbaceous/detrital diet.

Nonetheless, their young still need a lot of protein to grow and in the absence of food can start cannibalizing fast. The results of the experiments show that maximum growth can be achieved in the 35% protein diet.

Diet	Omnivore (as adults) Omnivore / Carnivore (as juveniles)
Plant Safe	No
Temperament	Very aggressive

For more information, read “Cherax Destructor Crayfish – Detailed Guide: Care, Diet, and Breeding”.

Marble crayfish (Procambarus virginalis or Self-cloning crayfish)

According to the scientific studies and experience of many aquarists, detritus and algae are the most important food sources in the diet of the Marbled crayfish.

Another fact that you have to keep in mind is that they also feed on plants (voraciously). So you will need to watch out when you are putting them inside any tanks that have live plants because they are going to eat them up without any hesitation.

Nonetheless, Marbled crayfish are not completely vegetarians. Once or twice a week they need to eat organic (protein-rich) food.

Diet	Detritivore / omnivore
Plant Safe	No
Temperament	Slightly aggressive

For more information, read “Marbled Crayfish – Detailed Guide: Care, Diet, and Breeding”.

Brazos Dwarf Crayfish (Cambarellus texanus) 

They are omnivores and prefer organic food. These species enjoy blackworms, crushed snails, earthworms, brine shrimp, etc.

Algae wafers, and vegetables should only be a supplemental diet. The main diet needs to be meat (protein) anyway.

Diet	Detritivore / omnivore
Plant Safe	Yes (with caution)
Temperament	Conditionally Peaceful

For more information, read “Brazos Dwarf Crayfish – Detailed Guide: Care, Diet, and Breeding”.

Dwarf Mexican crayfish (Cambarellus patzcuarensis)

They are omnivores and prefer organic food. As a special treat, you can feed your Dwarf Mexican crayfish Algae wafers, which is something they seem to really enjoy.

Many aquarists noticed that snails and any meaty foods are preferred and it helps them grow much faster. Algae wafers, and vegetables should only be a supplemental diet. The main diet needs to be meat (protein) anyway.

they are shrimp, fish, plants friendly (almost), and compatible with anything and everything.

Diet	Detritivore / omnivore
Plant Safe	Yes (with caution)
Temperament	Conditionally Peaceful

For more information, read “Dwarf Mexican Crayfish – Detailed Guide: Care, Diet, and Breeding”.

Cambarellus diminutus (the smallest known crayfish species in the world)

Cambarellus diminutus are extremely opportunistic eaters. It means that they can eat about anything edible they come across. 

They are safe to keep with any type of live plant. This species does not eat healthy plants and can, therefore, be kept in beautifully planted aquariums.

Diet	Detritivore / omnivore
Plant Safe	Yes
Temperament	Peaceful

For more information, read “Cambarellus Diminutus – Detailed Guide: Care, Diet, and Breeding”.

In Conclusion

If you are curious about what crayfish eat in the wild or in captivity, I hope this guide has provided the much-needed answers.

Feeding crayfish is no biggy since they are omnivores and quite receptive to a wide range of food items, be it veggies, fish foods, live, frozen or decaying foods.

While you’re at it, make sure to vary their diet, so they can obtain all the essential nutrients required to keep them healthy, active, and strong.

Related articles:

• Introduction to the Crayfish Care – Setup, Diet, and Facts
• How to Set Up a Crayfish Tank
• Can You Keep Crayfish With Other Fish.