The Blue Crayfish - Origin, care & breeding

Origins of the Blue Crayfish

The Blue Crayfish can be found in reference books with the latin name of Procambarus alleni, it has many common names including Florida crayfish, Everglades crayfish or even the Blue lobster. There is even an electric blue crayfish that displays a magnificent bright blue colouration. They are to be found naturally in North America, they are quite hardy and can live in areas where dry seasons provide little water for them to survive in, they overcome this by burrowing into the moist mud until the rains provide them with decent living conditions again.

The expected size of an adult male crayfish is probably about 5 inches (12-13 cm), selective breeding has produced a higher intensity of blue colouration for the aquarium but in the wild they are much duller in a bid to avoid predators. The Blue Crayfish are very territorial especially towards their own kind, often they will only meet as part of their breeding program.

Setting up an aquarium for the Blue Crayfish

When setting up the aquarium it is best to try to replicate their natural surroundings and also bear in mind that crayfish can escape very easily from an aquarium that offers them the opportunity. Always make sure that your aquarium has a tight fitting lid and that any areas where wires etc. for equipment are sealed with sponges or similar. The minimum size aquarium for the crayfish should be at least 20 gallons (90 litres, 24 US gallons), make sure that the aquarium has a decent sized footprint allowing the crayfish to roam. The substrate should comprise of fine sand or fine gravel as they have been known to burrow when they want to. They can adapt to variable conditions but the pH is best kept between 6.8-7.5, acidic water can be harmful to them if allowed to drop too low. The water temperature needs to be set between 15-24°C (59-75°F) and regular water changes must be performed to keep the water quality as high as possible. They will not tolerate any levels of ammonia or nitrites in the water so make sure that the tank is well matured before adding these to it. They do like to hide away at times so adding some form of cave will be invaluable, using un upturned terracota pot or a similar aquarium ornament will be beneficial.

The water must be well oxygenated, if the oxygen levels drop then the crayfish can “drown”, air pumps with bubble walls are ideal or a decent sized air stone will help with this, the outlets from the filters should also be aimed at the water surface to increase gaseous exchange.

Unless you have a large aquarium it is advisable to only keep one of these, as mentioned above they are very territorial and they are also predators. Only keep the Blue crayfish with tank mates that are active and fast swimmers, slower moving species can become a meal for the crayfish or at the very least become the target of attacks and become injured on a regular basis.

Feeding the Blue Crayfish

Never be tempted to overfeed your crayfish, this can lead to digestive problems so a couple of small meals daily is much more beneficial rather than adding large amounts of food in one feeding session. Shrimp pellets are ideal, one pellet per day is ample. The diet can be varied with vegetable matter such as lettuce, cucumber, zucchini, blanched peas etc. Always make sure that any uneaten food is removed from the aquarium before it decays as this will spoil the water and be harmful to the crayfish.

Breeding the Blue Crayfish

This is possible in the aquarium but is best left to experienced keepers as if the male is added into a tank with a female at the incorrect time after moulting he can become aggressive and tear the female apart. Sexing the crayfish is not that difficult if you know what you are looking for, the males are slightly larger than the females and if you hold them upside down you will see their sexual organs at the base of the tail. Sexual maturity is between 3-6 months and breeding is usually a quick process once the male and female are introoduced together. It is best to add them together for a couple of minutes initially to make sure that the male and female are both ready but keep a close eye on them incase you need to separate them before any injuries occur. The actual breeding process should take no longer than 30 minutes and the male will flip the female over to carry out the act. He will deposit a sperm sac which the female will use to fertilise the eggs that she already carries. The eggs are black in colouration and she can carry up to 200 in one batch, the expected fertilisation rate is usually about 100 eggs. She will carry the eggs on her swimmerets for approximately 25-30 days before they hatch and the young can be fed on finely crushed flake food.

The moulting process

All crayfish need to moult to grow, this process is repeated at a quicker rate the younger the crayfish, as they mature the growth rate naturally slows down and as expected the moulting process follows suit. Crayfish have exo-skeletons, they need to shed these to grow but this can be a stressful time for them as well as being stressful for the owners. They tend to hide away for a couple of days during the moulting process as they are at their most delicate directly after this process until the new skeleton underneath has hardened and can offer them protection. A perfect skeleton will appear in the skeleton and can often be confused with a dead crayfish for keepers new to keeping the crayfish.

It is best to keep the old skeleton in the aqaurium for a few days as the crayfish will nibble at this to replace lost calcium levels and make the moulting process go more smoothly, you can also add calcium supplements for the same reason.When the crayfish re-emerges you will see straight away that it has grown in size and the stress on yourself will be instantly relieved!

Special care tips

When adding the blue crayfish to the aquarium it is wise to hold it upside down just under the water level for a couple of minutes and gently rock the crayfish, this will ensure that no air bubbles are trapped on the underside of the crayfish which can cause problems if unchecked.

Ocassionally the crayfish may lose limbs, this can even happen during the moulting process, these will regenerate in time but make sure that the water quality is always high to prevent any infections setting in.

Never use copper based medications with crayfish, like all invertebrates copper can be lethal to these creatures.

Crayfish like to burrow in the substrate, vacuuming the substrate will also reduce the chances of infections to your crayfish.

Picture

Good image showing the anatomy: just click here, it's a PDF document.

Questions and answers

You're welcome to submit your own questions at the bottom of this page as long as the questions are unique and not yet answered on this page. Previously we were publishing some questions at aqua-fish.net/answers, but merged them with related pages later. On March 25th 2011 the following question was moved here.

• Question: Where can I buy a blue crayfish online?

  Answer: On 10/05/08 we were able to find blue crayfish for sale at www.aquariumfish.net for $30 USD.