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Cherax destructor is common in aquaculture and is gaining popularity as an aquarium species. So, if you are thinking of keeping a Cherax destructor crayfish (or Yabby) in your aquarium, you have come to the right place. Below is my complete care guide for Cherax destructor crayfish. It covers all aspects, from natural habitat conditions and how they should be translated within your aquarium, to dietary requirements and how to breed them.
Cherax destructor crayfish are easy to care for as they are very hardy. This species is an opportunistic feeder that can be found in a wide range of habitats and water conditions. In addition, it has an extended breeding period with multiple spawning events, a high spawning frequency, a rapid growth rate and the attainment of maturity.
Cherax is known for its abilities of hibernation and destruction it can cause as it can eat anything and can burry deep in mud or holes when required. When you’re done with this article you’ll find that you’ll be fully grounded in the art of keeping a Yabby.
Important: I want you to be fully aware that Cherax destructor is considered an invasive species.
| The U.S. Fish and Wildlife Service (in 2016 under the Lacey Act (18.U.S.C.42) (USFWS 2016a)) officially listed Cherax destructor as an injurious wildlife species.
As far as I know, It is unlawful to possess, import or sell Cherax destructor in Illinois, Pennsylvania, Ohio, Michigan. For example, the Florida Fish and Wildlife Conservation Commission has listed it as a prohibited species. Check your state laws before purchasing. NEVER release Cherax destructor into the wild! |
| Name | Cherax destructor |
| Common Names | Yabby, Blue Claw Fresh water, Blue Pearl |
| Scientific Name | Cherax destructor |
| Tank size (minimum) | 30 gallons (~120 liters) |
| Keeping | Easy |
| Breeding | Easy |
| Size | 10 – 20 cm (4 – 8 inches) |
| Optimal Temperature | 25 – 28 C (77– 82 F) |
| Optimal PH | 7.5 – 8.5 (7.0 – 9.0) |
| Optimal GH | 6 – 12 (3 – 22) |
| Optimal KH | 4 – 6 (2 – 18) |
| Optimal TDS | 150 – 300 (100 – 1000) |
| Nitrate | Less than 20ppm |
| Diet | Omnivore |
| Temperament | Very aggressive |
| Life span | up to 6 – 8 year |
| Color Form | Different color variations: green-beige, black, blue, dirty-white, light pink, orange, and light brown. |
Interesting fact: The term “Yabby” seems to derive from the word “Yabij “in the aboriginal language, which was used by wandering tribes to describe the native crayfish from central Australia. The generic name Cherax is thought to be a misspelling of the Greek word ‘charax’, meaning a pointed stake.”
This crustacean’s natural habitat is Southern Australia. They are commonly found on muddy or silted bottoms of streams, swamps, reservoirs, and rivers. Cherax destructors are rarely found in clear water habitats; they seem to prefer water with moderate levels of turbidity.
This species can also survive for long periods in areas where a body of water has dried up by lying dormant in burrows in the mud.
The head and internal organs of all crayfish are protected by the carapace and the six segments of the abdomen are individually encased with a flexible membrane between them to allow movement.
Their eyes are not their best sense, the senses of touch and taste are far more important, and are perceived using a pair of large feelers (or antennae) and a pair of small, fine, centrally located feelers (or antennules).
The color of the Cherax destructor is highly variable and includes green-beige, black, blue, dirty-white, light pink, and orange forms in addition to the more common light brown.
The type that is bred for the aquarium trade is often bright blue. Their specific coloration can vary widely depending on water conditions, season, diet, environment, and genes.
Yabbies grow pretty big and range from 10-20 cm in length about 4-8 inches. Most Cherax destructor can grow from juvenile to over 15cm (5.9″) in time as little as 12 months. Fully grown, they can weigh up to 350g.
Cherax destructor has a relatively long life span (from 3 to 6 years), compared to other crayfish species. However, there are also reports that some individuals lived up to 8 years.
Cherax destructors can be great aquarium pets if you understand their natural tendencies and behaviors and care for them accordingly.
First of all, they are extremely efficient diggers. Actually, this is why it got the name “Destructor” – because of the damage, it can cause to dam walls and levee banks after burrowing. It buries itself 0.5-2 m deep in the mud or the holes and able to survive several months in the burrows.
Cherax destructor is a nocturnal species. Feeding behavior is mostly controlled by the amount of light filtering through the water and it is often found that the greatest periods of activity occur shortly before dawn and just after dusk.
These crayfish are very aggressive and territorial with their own species.
The Cherax destructor needs to shed its exoskeleton to grow, so be sure not to confuse this for a deceased yabby. Also, take care not to discard the exoskeleton as the yabby may will it to recycle the calcium and other minerals.
The frequency of molt depends on age and temperature. Baby Cherax destructors can molt every 5 – 7 days, juvenile yabbies usually molt every 3 to 4 weeks and the length of time between molts will increase as the crayfish gets older. Adult yabbies only molt 1 or 2 times a year.
Most metabolic activities are reduced during the pre-molting process. So, if you see that your crayfish does not eat as it used to – this can be the sign of molting.
After removal of the old shell, Cherax destructors will need a place to hide till it’s new shell has hardened. Keep in mind that freshly molted crayfish are exhausted, stressed, and vulnerable to predation due to the lack of protective covering.
After molting, the metabolic demand (to harden the shell) for calcium is particularly great. Crayfish use calcium to produce a new and healthy shell. I highly recommend reading my article “How to Supplement Shrimp and Snails with Calcium”. These nutrients are necessary in abundance especially following the molting of your crayfish.
You can read more about molting in my article ”Crayfish and Molting Process”.
No, Cherax destructor is not plant safe. It is absolutely not possible to keep them in planted aquariums. They will eat, cut, shred, and uproot everything if it is possible. They are lawnmowers.
Note: Only floating plants can be relatively safe with the Cherax destructor.
Note #2: If you need a plant safe crayfish, check out my guide “Dwarf Mexican Crayfish – Detailed Guide: Care, Diet, and Breeding”.
Cherax destructor is an opportunistic and omnivorous feeder. Although plant material and detritus often dominate the gut contents, it will eat anything it comes across. Their diet includes plants, algae, animal detritus, macrophytes, dead and live animals such as snails, fish frogs, insects, tadpoles, fingerlings, etc.
According to different studies, in the wild, Cherax destructor species has 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.
They will act as a scavenger in the aquarium, eating any food that comes to rest on the bottom. So you can decide to add quality sinking pellet and meaty food such as fish fillets to their regiment. They can eat any kind of leaves and other plants that they will find in the water.
Within the aquarium Cherax destructor can be fed a variety of foods:
Ensure that the diet of your pet crayfish is rich in nutrients, especially calcium. A lack of calcium in the water results in soft-shelled yabbies.
Important: You must take note not to overfeed your yabby. They possess a small stomach and will stop eating when full, leaving the remainder of the food. It’s also not necessary to feed them every day. You can adapt the routine of feeding them two small pieces of food every two to three days. For a healthy habitat for them try to clear away any left-over food for two hours.
Air is a must necessity to any living beings. In order for Yabbies to grow well, continuous aeration is required to maintain the level of oxygen in the water. Try and make the water properly aerated by using the proper equipment.
Regardless of their hardiness, it will be better to acclimate them (read more about it here) as all invertebrates.
Tank Equipment (links to check the price on Amazon)
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The sex of Cherax destructor can be determined externally:
If you are trying to breed yabbies, it is fairly easy and is usually achieved through simple co-habitation of the tank.
Cherax destructor females become sexually mature when they are about 1 year old and approximately 6 – 10 cm (2 – 4 inches) in total length.
The male yabby will flip over the female and deposit a sperm packet near the female’s reproductive organs. Next, the females produce eggs that will cross through the sperm packet, fertilizing them.
Cherax destructor females keep fertilized eggs at the underside of the tail until they hatch 8 – 10 weeks later. Berried females use their pleopods to keep eggs cleaned and well oxygenated.
The eggs are approximately 2 mm in length and oval in shape, they are usually olive green in color.
The average clutch size is 350 – 450 eggs. Female fecundity increases with body size, reaching up to more than 1000 for a large female.
The eggs are normally incubated within a time span of 19 and 40 days depending upon temperature. For example, in water temperatures of 20°C (68F), the eggs hatch within 40 days. As temperature increases, the length of time taken to hatch decreases until water temperatures reach 30°C; temperatures above 30°C adversely affect hatching.
The species has high parental care of their young. After hatching, newly hatched Cherax destructor babies are still attached to pleopods (swimmerets) on the female’s abdomen. She will carry the young and release them when they reach stage 3 juveniles. In newly hatched yabbies, molting may take place every 4 – 5 days.
Note: When the young leave the mother, the female Cherax destructor can mate again because her ovaries are held almost in a constant state of readiness.
Once the babies leave their mother, you will need to transfer them into a separate tank with lots of hiding places. It will help you to prevent any aggression from her side.
Note: Of course, you can also separate the berried female from the main tank and then put her back.
Tiny Cherax destructor will 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.
While they are small, Cherax destructor can co-exist with other aquatic inhabitants. However, in time they start to actively hunt most tank mates including fish, crustaceans, and snails.
You should know that yabbies are bottom dwellers and will eat anything they can catch. So because of these, you shouldn’t keep them in the same aquarium with small fish (especially bottom-dwelling fish) as these are easy prey at night time for this species.
They will eat any passing fish they can catch. So it’s advisable to place only one species in a tank.
Read my article “Can You Keep Crayfish With Other Fish?”.
Cherax destructor will eat your snails. So, do not keep them with any decorative snail species like Nerite Snail, Rabbit Snail, Mystery snail, etc.
If you are ready to lose shrimp from time to time, you can keep them with cheap species like Cherry shrimp.
In general, I would not advise keeping Cherax destructor and dwarf shrimp together, especially with Bamboo shrimp and Vampire shrimp. Due to the unique food intake technique (these shrimp stay motionless), they can be an easy target for the crayfish.
Cherax destructor is also cannibalistic, particularly in overcrowded situations or if there is insufficient natural food available. Animals that have recently molted are more susceptible to being cannibalized.
Therefore, it can be risky to house multiple crayfish in the same tank. Males, in particular, are extremely likely to fight and eventually kill one another when housed together. Multiple Cherax destructor should be kept only in groups of one male with one female.
Do not keep Cherax destructor and frogs (for example, African Dwarf frogs) together. They will hunt them down and eat them. According to the New South Wales Government (Threatened Species Conservation. Act 1995), there are 29 endangered frog species because of the Cherax destructor.
Do not keep Cherax destructor and tortoise together. Yabbies also showed strongly aggressive and predatory behavior towards tortoise hatchlings in a laboratory study.
Do not worry. Yabbies like most crayfish possess the ability to regenerate lost limbs, a handy trick considering limbs and claws are often lost during fights with other crustaceans.
These lost body parts start to grow back at the next molt, however, total regeneration is not immediate and may take several molts to complete. The process of regeneration goes slower as the yabbies grow in age.
Cherax destructor is very easy to care for due to the high fecundity, quick growth rate, feeding habits, and extreme tolerance of the species. It can be a great addition to the aquariums of both beginners and experienced aquarists (if this species is not prohibited by your state law).
Introduction to the Crayfish Care – Setup, Diet, and Facts
How to Set Up a Crayfish Tank