What Do Crayfish Eat?

What Do Crayfish Eat?

Crayfish are a fascinating addition to a freshwater aquarium, and many people find them more active and interesting than shrimp. They come in a vast range of sizes with many beautiful color morphs and are hardy and interactive pets. But what do crayfish eat, and how do you feed them? Let’s learn more about how to keep crayfish in an aquarium.

Overview of Crayfish

Crayfish are freshwater crustaceans, closely resembling their big cousins, lobsters. Members of the crayfish family can be found worldwide, living in flowing freshwater streams and brooks or marshy swamps and ditches.

Because they live in so many places, they have a wide range of common names, including crawfish, crawdads, yabbies, mountain lobsters, and mudbugs.

Crayfish spend most of their time walking on the substrate but can use their abdomen to quickly swim away from a predator. Some are also avid climbers and will explore every part of their plants and aquarium décor.

They are scavengers and opportunistic eaters, surviving on all kinds of living and decomposing plants and animals in the water.

As aquarium pets, crayfish come in a wide range of sizes and colors, from less than 1 inch to more than 6, and from bright red or blue to pale pink or white. Some variants are especially known for being aggressive and may eat plants or even their tank mates.

What Do Crayfish Eat?

In the Wild

Crayfish are omnivores and will eat plants as well as animals. They will eat living and dead organic matter and feed on various detritus in the water.

In the wild, crayfish will feed on decomposing plant material in the water, ripping off soft bites with their claws. They also eat algae, bacteria, snails, and all kinds of decomposing material. In other words, if a crayfish can catch it, a crayfish will eat it.

While crayfish eat meat and enjoy insects, larvae, and even other crayfish when they are vulnerable, crayfish survive primarily on plants and algae. Protein is a relatively small proportion of their diet.

In the Aquarium

In the wild, crayfish will try to catch small fish with their claws but are seldom successful because they are usually outswum by the fish. However, in an aquarium, where there is less room for a fish to escape, they are more successful hunters.

Because their natural diet is so varied, and they aren’t fussy about food, they are relatively easy to feed in an aquarium. Here’s what to feed a pet crayfish:

Living Plants

Crayfish are active plant eaters, but vegetation is natural and healthy for them. Living plants also help to re-create their natural habitat and make them more comfortable. Choose fast-growing, resilient plants like hornwort and java moss for the crayfish to eat and hide in.

Vegetable Scraps

If you have any vegetable scraps left over from your kitchen, give them to the crayfish. They particularly like leafy greens, but any kind of vegetable will be eaten, and they add variety to their diet.

Pellet Foods or Wafers

Almost any kind of fish food will be eaten by a crayfish, particularly if you get pellets that sink to the bottom. These are a good source of protein, which crayfish especially need when they are young and growing.

Live Food

If you choose to feed a crayfish small live food like small fish, shrimp, or bloodworms, it adds protein to their diet, and you can also observe their hunting behaviors.

Algae and Bacteria

Finally, avoid overfeeding your crayfish so that they will still eat tank algae and help to keep their environment clean. Some crayfish are even filter feeders, automatically removing bacteria from your aquarium water.

How Often to Feed Crayfish

For a healthy adult crayfish in a tank with lots of plants and algae, you only need to offer a food pellet or wafer every other day to meet their nutritional needs.

Depending on the pellet size, you may even pinch it in half. If the crayfish doesn’t finish the pellet within 15-30 minutes, reduce the amount you offer them.

You may also give them a leaf of lettuce or spinach, a couple fresh peas, or a slice of carrot or zucchini every day or two for variety.

Crayfish are fun and interesting additions to an aquarium, and they come in a range of sizes and colors. They are hardy and low-maintenance pets and may even take care of some of your kitchen scraps for you. Their natural diet is so varied that there is almost nothing you can’t feed a crayfish.

What Do Crayfish Eat


Can Crayfish Eat Apples?

A crayfish will definitely eat an apple. Depending on where you get the apple, it’s a good idea to wash and peel the apple first, to remove any pesticides, waxes, or residue on the surface.

Will Crayfish Eat Egg Shells?

Crayfish need a good source of calcium to build and maintain a robust and healthy shell. While young, a crayfish may molt every week or two, while a healthy adult may molt every month or two.

They need hard water, iodine, and calcium to build a strong shell and molt successfully. If the water is high in calcium, a crayfish may naturally absorb some as they live and browse in the tank, but offering additional calcium sources is a good idea.

There are many ways to help give crayfish the calcium they need. Here are a few recommended methods

Feed Crayfish Vegetables High in Calcium

Collard and turnip greens, spinach, kale, broccoli, squash, and parsley are naturally high in calcium.

Offer Calcium-Rich Food Supplements

Many foods designed for crabs and shrimp are high in calcium and can be an excellent crayfish choice. These supplements often have several other ingredients and trace minerals to support strong shells, vibrant colors, and overall health.

Add a Cuttlefish Bone

Cuttlefish bones are practically all calcium and are popular for birds, so they are often easy to find in pet stores.

A cuttlefish bone will slowly release calcium over long periods when placed in a tank; they are great for a crayfish’s long-term health but won’t solve immediate concerns. Add a small 1-inch piece of cuttlefish bone at a time and wait for it to dissolve.

Tums Antacid

Tums antacid tablets are made of calcium carbonate and dissolve quickly, affecting water quality right away. A crayfish may eat a Tums tablet, or it may simply dissolve in the water and add calcium. Use Tums with caution because they quickly affect water quality.

Egg Shells

Eggshells are incredibly high in calcium but should be treated before being added to an aquarium. Eggshells are high in a range of bacteria that can harm your aquarium. To use eggshells for your crayfish:

  • Boil the eggshells for 5-10 minutes to kill bacteria
  • Allow them to dry completely
  • Microwave them for 5-10 minutes until they are completely dry and brittle
  • Remove the inner shell membrane if any of it remains after microwaving
  • Grind eggshells in a coffee grinder until they are pulverized into dust
  • Sprinkle some of the powdered eggshells into your aquarium

There are many ways to give your crayfish the calcium it needs to molt successfully and build a strong shell. Eggshells are a good solution, but there are a lot of other options as well.

Can Crayfish Eat Fruit?

Crayfish can eat fruit, although fruit often doesn’t have as many healthy minerals like vegetables. Be mindful of acidic fruits like citrus, pineapples, grapes, and pomegranates because they may affect your aquarium’s pH.

What Vegetables Can I Feed My Crayfish?

Crayfish can eat almost any vegetables, although it’s a good idea to offer vegetables naturally high in calcium and minerals. They also like vegetables that are a little bit spoiled and naturally sink to the bottom of the tank. Some good vegetables for a crayfish include:

  • Leafy greens
  • Zucchini
  • Blanched carrot
  • Peas
  • Squash
  • Green beans