The marbled crayfish is a unique little critter. Each of them produce offspring all by themselves, much in the same way that many plants can produce seeds without the aid of another plant. Each one of the marbled crayfish is a female and when kept healthy the crayfish will multiply again and again producing babies that look just like the mother. The great news is that they are easy to keep and a lot of fun to watch as well.
The marbled crayfish is a medium-sized crayfish. Most females only get about 4 inches with a few getting a little larger than this. Because of their size many people try to put them into small spaces. However, because crayfish are messy creatures (produce a lot of waste) it is a good idea to put them in as big of a tank as possible. If you want to have a large colony versus one or two you will want even more space.
- Minimum: 10 gallons – This is really my opinion and keeping a 10 gallon tank clean with marbled crayfish isn't easy. However, it can be done. That being said, bigger is better.
- Better Size: 40 gallons or more – If you are planning on having a large colony or more than one breeding adult then it is very important that you give them more space. A larger tank will also make it easier to keep the water quality high.
- Other Things to Add to Their Space – Fine gravel or sand is good for the bottom of their tank because it makes it easier for them to find their food and forage. Lots of hiding places are also appreciated. You can use PVC pipe to make tunnels or hook them together to make stacks of “apartments” or “hotels”. Shells, rocks, driftwood, and other decorations can provide more shelter, give you the look you want, and help you to grow a really good bacterial filter (to help keep the water clean).
Most crayfish are dirty and produce a lot of waste. That being said, the marbled crayfish is even worse because it multiplies very quickly and seemingly endlessly. Unlike some crayfish the marbled crayfish don't eat their children or sisters. This allows the population to keep growing and growing which can be bad for water quality. By following these tips you can keep your water cleaner than you would other wise.
- Substrate - A good substrate will really go a long way in helping to keep your water clean. You need a really good bacterial filter to deal with all the waste produced by the crayfish. The bacterial filter will grow on everything in the tank including the gravel and other substrate. A good gravel on the bottom and sand on the top can really help. Some people also like to add an undergravel water filter.
- Filter – You should have at least one filter that is designed to filter a tank twice the size of the tank. If you can, two filters is a better choice. Often times you will get the best results with one over the back filter and one internal filter such as a sponge filter. Whenever there is an intake valve you should make sure that you cover it with pantyhose, a filter sock, or another cover to prevent baby marbled crayfish from getting sucked up.
- Water Changes – You should give the tank a regular water change. As much as 90% of the water can be removed without harming the fish. You should not scrub the glass, clean the filters, or do any other cleaning on the same day that you do the water change. To do the water change leave all the fish and crayfish in the tank, use a cup or a siphon hose to remove the water, and fill it with fresh water. If using water straight from the tap make sure that you are using a dechlorinator to protect your fish and crayfish from the chlorine found in tap water.
- Live Plants- Live plants always help with the water quality. To keep large plants in a crayfish tank you will want to make sure that you are feeding all the fish well. Floating plants often fare better, but you can try a variety. Having a house plant that grows out the back of the tank can be a great choice, but make sure that the crayfish can't climb up and out of it. You can also try a few plants like java fern which is eaten less often. However, note that whatever you put in there shouldn't be valuable or something you will cry over if it does get eaten. You will also want to give a great light for your plants so that they can grow as much as possible before they are nibbled on.
Feeding marbled crayfish is really easy. The babies and the adults alike eat a variety of foods. They need a lot of plant matter which can be supplied by a high quality fish food. You can also supply them with plants that they like such as anachris and even duckweed. You can also put in blanched or weighted down vegetables in their tank. They love canned green beans, blanched zucchini, and weighted down cucumbers.
While they are primarily plant eaters, they do need protein. This can be provided with high quality fish food, algae fish food or powders, and meat. Some great examples include blood worms (frozen or freeze-dried), brine shrimp, and even thawed (previously frozen) seafood such as shrimp or clams. You can also feed them snails. Some say that the snails will be eaten if they are tossed in there. However, my crayfish don't eat any snails in their tank. Crushing them will allow the crayfish to eat them even if they don't want to hunt them. If they don't get enough protein they are less likely to have babies.
Marbled crayfish can be kept with some fish. You can't keep them with fish that will hunt down and eat a crayfish. This includes cichlids who will gladly consume as many crayfish as they can find that will fit in their mouths. Even smaller fish will much on baby crayfish, but they won't do enough damage to not have the crayfish multiply quickly once they reach adulthood and are well fed in a tank with clean water.
You should also avoid keeping them in tanks with fish that have a lot of fancy fins because they will nip at them and cut them up. Finally they should not be kept in tanks with other bottom feeders. They can be territorial and will nip at fish in their space which often includes fish that live on the bottoms.
Good fish to keep them with include small livebearers such as wild or short finned guppies and platies. You can also keep them with the tetra species. You can make a nice community tank from peaceful fishes.
Uses for Marbled Crayfish
Marbled crayfish can quickly over populate your tanks. You want to make sure that you have a plan to get rid of them or you won't be able to keep them all. One female can produce 20 to 200 or 300 babies depending on her age. In five months those females can turn around and produce 20 or more babies. It's a good idea to have a plan for the offspring when you get your first crayfish (or two).
- The self cloning crayfish is a great feeder. You can feed larger ones to large cichlids and puffers. Smaller ones can be fed to smaller fish. For those fish that can't eat a crayfish whole you can chop the crayfish up and feed them that way.
- Self cloning crayfish also make great choices for bait. You can use them as live bait for fishing in the ocean. They can also be frozen and used in freshwater fishing as well.
- The marbled crayfish produces a lot of waste, is easy to raise, and keeps on multiplying making it a great choice for aquaponics. The waste from the crayfish makes for a great choice for growing lots of healthy plants.
- You can also give the marbled crayfish away to those you trust to take care of it and who won't release it. You can also sell the crayfish to those who are interested in owning it.
Whatever you do, do not release the marbled crayfish into local waters. They can have a horrible effect on the ecosystem and even have the potential to be an invasive species.
The marbled crayfish can make for a great aquarium species. It is hardy and pretty easy to take care of. In fact, once you get their tank set up the way that the crayfish need then you will be able to keep the crayfish easily and get them to multiply! You will be having lots of marbled crayfish in no time at all.