If you’re interested in bringing home a bright blue freshwater critter for your aquarium, you’re in luck. The blue crayfish is a freshwater aquarium pet that hobbyists can enjoy at home.

The vividly colored creatures (sometimes called electric blue or freshwater blue lobster for its vivid shading) are fairly easy to care for.

They also add a lot of fun to the life if your fish tank and get along well with a lot of popular fish species that aquarists love.

Let’s take a look at the best care practices for these little guys.

Quick Intro to Blue Crayfish

blue crayfish
Family: Cambaridae
Scientific Name: Procambarus alleni
Other Names: Electric blue crayfish, Florida crayfish, Blue lobsters, Everglades crayfish, Sapphire crayfish, blue freshwater lobster
Care Level:Easy

Natural Habitat, Identification, and Where to Buy

In nature, Blue Crayfish are found in a variety of places. They can live in freshwater marshes, streams, wetlands, flood plains, and even ditches with enough water.

This fish is primarily located in the southern part of Florida, in the panhandle. The waters they occupy in Florida cover east of St. John’s River, south of Marion and Levy Countries.

This species also ranges south as far as the Florida Keys. There have been colonies of fish released from aquariums in Germany, California, and France.

This species lives in water that has a minimum amount of flow and movement. They can survive extended dry periods of no water by burrowing into mud, clay, or sand to stay hydrated.

Several of the waterways that the Blue Crayfish live in are filled with brackish water that has a salinity that is upwards of eighteen parts per one thousand.

The Blue Crayfish is an average size for crayfish. In captivity, they typically grow between four to five inches in length. There have been some crayfish in the wild that have grown up to seven inches long.

With the right care, the Procambarus Alleni Blue Crayfish can live upwards of five years. The right care includes making sure the crayfish has a high-quality diet and that the water is kept consistently clean.

This species of crayfish is found in a variety of colors. They appear in a variety of shades of brown, red, orange, and the most common color being brilliant blues.

It is common for this species to also be speckled with dots or light patches The blue colors have become the more common version of this species because fish breeders have concentrated their breeding efforts on their coloration.

You can purchase blue crayfish online:

Optimal Water Conditions for Blue Crayfish

Water Temperature: 65-75°F
Water Flow Rate: Low to minimum
pH: 6.5-7.5
Water Hardness: 3-10 dH

Tank Setup

Close up of a big blue lobster with huge tentacles next to rocks and corals in an aquarium.
Minimum Tank Size: 20+ gallon tank
Optimal Tank Size: 30+ gallon tank
Optimal Tank Shape: Square or rectangular
Recommended Filtration: HOB or canister filter

When putting together the tank for your Blue Crayfish, you will want a tank that holds a minimum of twenty gallons for one crawfish. If you pick a smaller tank it will only create problems for you and your crustaceans

If you decide to place more than one crayfish in the same tank, you will need a larger tank, at least 30 gallons. The crayfish in your tank must be around the same size and of different genders or you will have some major problems.

Top tip: If they are the same gender and/or one is significantly bigger than the other, the crayfish will fight and most likely the smaller will be eaten by the larger.

Your crayfish need to have space for exploring and claiming their territory. Plus, it helps if you have room to maneuver around the crayfish while managing the water and cleaning things up.

As you pick your tank, make sure that there is a quality lid that matches the tank and fits securely. Crayfish can and will climb around their tank, but they are not strong enough to lift the lid on a tank.

The crayfish has strong claws that can create some issues while putting your tank together. You will not be able to get a sponge filter to last long if the crayfish decides it needs to be cut up. Instead, try using a canister or HOB filter.

The important thing is to have a filter that can handle all of the waste that a crayfish creates.

Crayfish do like sluggish water, but you still should consider investing in either an air stone or air pump. The water needs proper oxygen otherwise certain crayfish, like the Electric Blue, will die without the additional oxygen.

If you don’t want to spend the extra money that an air pump will cost you, you will need to make sure you build your tank differently.

Top tip: Place rocks so that your crayfish can climb out of the water and breathe as needed. If you have multiple crayfish, make sure there is plenty of room for all of them to surface and breathe at the same time.

An aspect of water care you need to be concerned about is called Total Dissolved Solids (TDS). This is a measure of everything that has been dissolved in the water you are using.

Invertebrates are very sensitive to what the water may contain. Ensure the TDS is in the 150-200 range. This number can increase too high if the water in your area has too many minerals in it.

To compensate for this, use de-chlorinator to bring the numbers down. If nothing else, you can always just use distilled water as an alternative water source.

Author note: It’s very important to keep nitrates and ammonia as close to 0ppm as possible. It doesn’t hurt to test the water frequently so that if there are any issues you can take steps to correct them.

Creating the Landscape

blue crayfish

When choosing substrates, a lot of people choose to use colors that help their crayfish stand out the best. Cobalt is a popular choice, but the aesthetics you choose should be the ones that make you happy.

Gravel and sand both work equally well in your tank. The one advantage of using sand is that your crays will sometimes take the opportunity to burrow into the sand.

When you are choosing the décor for the tank, the biggest requirement is that crayfish need places to hide.

When Blue Crayfish molt their exoskeleton, they become vulnerable and feel the need to hide. It is important to give them a place they can go to during this process.

Making places for your crayfish to hide is relatively easy because there are so many options. You can use material such as driftwood, PVC tubes, or even overturned pots.

If you want something premade there are plenty of pet stores that sell artificial caves (hiding places) that will work.

Whatever you decide, the important thing is that the cave is big enough to allow them to hide from any of their tank mates.

If you do decide to house multiple crayfish together, each one must have a place to hide that is in a different spot from the others.

Crayfish become very territorial and do not like to have neighbors and will not play nice if they feel they are being invaded.

An important part of the tank is including live plants. These plants will look good, help the crayfish feel at home, and help with the tank’s nitrogen cycle.

Author note: One of the problems you may encounter is that the electric blue crayfish can be rough on any plants you have. They are known to uproot, tear apart and eat the stems of plants as they go about their normal routines.

If you want plants that are (mostly) sage from crayfish plant violence, floating plants are a great choice. If you do not like floating plants, others you can consider using are Java Fern, Marmo Moss, Anacharis.

Best Plants: Floating plantsJava Fern, Marmo Moss, Anacharis
Best Lighting: Low light, don’t use a hood light in the tank
Best Decorations: Artificial cavesdriftwood, PVC pipe or even overturned pots
Decorations to Avoid:Anything your blue crayfish and crush with its claws

Physiological Considerations for Blue Crayfish

Size: 4-5 inches
Lifespan: up to 5 years
Temperament: Very aggressive
Preferred Tank Region:They tend to split their time between the bottom of the tank and onshore
Scale Thickness:n/a
Gill Considerations: n/a
Swimbladder Considerations: n/a
Fin Shape Considerations: n/a

Blue Crayfish are known for resembling small lobsters. When you compare them to their ocean living cousins, they are much shorter. On average Crayfish will reach 4-6 inches long.

An important part of the crayfish’s life cycle is that it will molt at different times. When this happens, it will need a place in the tank that it can hide in and feel safe.

During the first few months of life, crayfish will molt frequently. Once the crayfish has reached maturity, this will slow down.

The signs of molting are about to begin is that they show a lack of appetite and will be less active. During this time the crayfish focus on ingesting calcium.

This means that it is important to make sure your crayfish has plenty of sources of calcium to consume, otherwise, their molt might be incomplete.          

While growth in Crayfish is a complicated and asynchronous process, it roughly follows a pattern. When they are babies, they will molt every few days.

For juveniles, they molt about every one to three weeks. The adults will moly every four to eight weeks.

Once the molting ends it takes around three days for their new exoskeleton to harden.

The Electric Blue Crayfish has a typical lifespan that is between five to six years long. To help your crayfish, have a lifespan that is on the longer side, requires constant vigilance with keeping their tank water quality high.

If the water quality dips, your crayfish will likely suffer from ammonia poisoning. If they get sick from ammonia it will create lifelong problems that will ultimately reduce how long they will live.

After the Blue Crayfish finishes molting, they will eat their prior exoskeleton. This is done to make sure they do not lose the nutrition that was in it. There is no need to feed the crayfish for several days after the molting.



It is not suggested for an inexperienced fish keeper to house multiple Blue Crays in the same tank.

There are a lot of problems that can arise, and it helps to have previous experience from managing a single Blue Cray before trying multiple.

While electric blue crayfish may not get along with others, there are still ways for them to have freshwater fish tankmates. Despite claws, aggression, and the ability to climb, some tankmates do well together with crayfish.

While they are not particularly fast, Crayfish will swipe their claws at anything that swims by them. Keep in mind that Crayfish are not particularly good at protecting themselves against predators.

Freshwater shrimp and snails are two species that should not be placed in a community with Bluefish Crayfish.

Crayfishes are known for being opportunistic eaters and will assume your shrimp and snails (not to mention any other small invertebrate added to the tank) are a snack.

If you want to include fish you will want to have fish that can swim fast. Another important quality to have in fish tankmates is to choose ones that dwell in the middle and top of the aquariums.

Top tip: You do not want to choose fish that are aggressive because they will swim right at the crayfish and get hurt or killed.

Some of the fish that match this criterion such as Rainbow Darters, Hatchetfish, Danios, and Tiger Barbs.

Crayfish are known for not having good temperments. However, it is possible to house multiple ones in the same tank as long as you have enough space for them.

They are a very territorial animal and if there isn’t enough space there will be fighting and possible deaths.

After you decide how many you want to house in a single rank, it is important to purchase all of them at the same time. If you introduce a new crayfish after everyone else has established territory then the new guy will have troubles.

Putting them all in the tank at the same time prevents this.

Gender, Breeding, and Reproductive Considerations

Crayfish’s inability to get along extends to the mating process. After they mate, the two crayfish are likely to get aggressive and start fighting.

Due to this aggression, some fishkeepers will set up a tank specifically for the two to mate, and then for the female to carry around the eggs, hatch them, and then remove her when she becomes too aggressive.

After the process, the female will carry the fertilized eggs around under her tail for about a month. When the babies hatch the mother releases hormones that encourage them to stay close so she can take care of them.

The hormones stop after three days and she needs to be removed or she may end up eating them.

When the mom is removed it is up to you to take care of the baby crays. You can feed them baby brine shrimp, crushed pellets, or spirulina.

Nutritional Needs

In the wild, Electric Blue Crayfish are scavengers who are happy eating whatever is available. This desire to eat whatever can make them easy to feed. However, this doesn’t mean you should feed them anything.

You should feed them high-quality food (ideally shrimp pellets or similar) and a well-balanced diet so that they can be healthy and molt with no troubles.

There are multiple commercially available foods that you can give Crayfish. Sinking pellets, Algae Wagers, and Spirulina Flakes are all good choices.

When feeding, only feed them once per day and only as much as they can eat.

If you want to give them a treat or feel they aren’t getting enough protein, you can feed them live, frozen, or freeze-dried foods. So great choices include dwarf shrimp tails, blood worms, black worms, and crab pellets.

Vegetables that have been blanched and peeled are another good choice. There is a wide variety you can pick from but carrots, cucumbers, lettuce, spinach, and zucchini are some of the more popular.

You must have a quality calcium source because it aids in crayfish growing their new shells. You can feed them calcium supplements to help them.

Best Sustenance Food Type:sinking pellets (shrimp pellets in particular), spirulina flakes
Additional Food For Optimal Health:add in algae wafers, bloodworms, and crab pellets
Special Foods and Considerations for Best Color and Growth:Vegetables and algae wafers balanced with high protein foods
When and How Often to Feed Fish Based on Life Cycle:They should be fed once per day

Common Diseases and How to Avoid and Treat Them


When Electric Blue Crayfish become exposed to ammonia or nitrates they become stressed. Stress leads to immunity decrease and the possibility of infection.

To keep your water qualities high, it is important to conduct water changes of 25% every week.

If you introduce wild-caught crawdad to your tank they could bring a mold that causes crayfish plague. This attacks their brain and nerve cord. As the disease progresses the crayfish will show signs.

This disease is highly infectious and once a crayfish shows signs, odds are any other crayfish in the tank is already infected.

There are no drug treatments for this disease so the only thing you can do is make sure you do not introduce wild-caught crayfish to your tanks.

Best Antibiotics: None
Treatments to Avoid:n/a
Food Recommendations When Sick:n/a
Hospital Tank or Isolation Withing the Community Tank: They should be kept in an isolation take when ill.

4 Facts About Blue Crayfish

  1. Crayfish are known to be super aggressive and omnivores, this can lead to them trying to eat each other.
  2. Blue crayfish are known for having beautiful colors but they are known for having worms live in their pinchers.
  3. Crayfish lack a gene and that causes their exoskeleton to turn cobalt blue.
  4. Blue crayfish come from freshwater streams and wetlands primarily in Florida, but they have been found in California, France, and Germany.

FAQs About Blue Crayfish

Blue crayfish in the aquarium

How rare are blue crayfish?

These genetic oddities are technically a color morph of the common brown papershell crayfish. They lack a certain gene which results in them turning blue.

Some of these varieties of blue crayfish are quite common (procambarus alleni as morphs) in the wild and in farms. They are more common in the farms than in the wild, though.

Do crayfish eat each other?

Since most crayfish are aggressive (excessively so in some cases) and omnivores, it is not uncommon for crayfish to eat each other if they’re dominated and killed a fellow crawfish.

This is why it’s important to house them appropriately (see suggested guidelines above in the “society” section).

Are those worms I see in their claws?

Gross as it might seem, yes, you could be seeing worms living in the claws of your crayfish. For whatever reason, worms often will make crayfish pinchers their home.

You don’t need to be concerned, however, as the worms don’t harm the crayfish.

Why are they called blue lobsters if they’re crayfish?

Blue crayfish are often called blue lobsters in the aquarium industry. Why? Because in the industry the name “lobster” has been given to crayfish.

This doesn’t reflect reality, however: they are crayfish and not actually lobsters, which are marine animals.

Can crayfish come out of the water?

While they can’t live their entire lives out of water, crayfish have been known to live on land for a few weeks.

The primary thing is that they require water to keep their gills wet.

And technically, yes you can hold or even play with your crayfish (in a dish with some water in it, for example), but it’s not recommended for the well-being of your crayfish.

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