Crayfish – The Care, Feeding and Breeding of Freshwater Crayfish (Crawfish)

Quick Stats

Minimum Tank Size: 5 Gallons
Care Level: Easy
Water Conditions: PH 6.5-8 and Medium Hard to Very Hard
Temperature: 65-75 F (18-23 C)
Maximum Size: 3 inches (8 centimetres)

Introduction

For anyone looking for a quirky and interesting pet, the freshwater crayfish is an excellent choice.. They are easy to care for, extremely hardy, and often interact with their owners. While crayfish are definitely not safe for a community fish tank, it is well worth having a tank dedicated to crayfish just to enjoy their antics.

When choosing a freshwater crayfish, it’s important to know that there are well over 100 species of crayfish from around the world. While most crayfish require cool water, some require ¬†tropical temperatures to thrive. Before purchasing a crayfish, a owner should do some research to determine the crayfish species needs. If a crayfish is well cared for, they will usually live 2-3 years, with some species living even longer.


Housing

A single crayfish can be kept in a relatively small aquarium. A 5 to 10 gallon aquarium is usually more than adequate, especially if regular water changes are provided. Crayfish are notorious for hiding their food, and will often have a stash hidden away in a cave or flower-pot. On top of that, they are also messy eaters, and when coupled with hidden food , water quality can quickly decline. When doing water changes, you should always check for a stash of food in any of the crayfish hiding spots.

If more than one crayfish is going to be housed in a tank, then a minimum of 20 gallons need to be provided. Crayfish are cannibalistic by nature, and when a crayfish moults it is nearly defenseless until its shell hardens again. During this time, it will hide for a few days, so don’t be too alarmed if a crayfish disappears for a up to a week at a time. Because of this, it is very important to provide numerous hiding places and enough space for each crayfish in the aquarium -¬† unless someone wants their crayfish to become an expensive meal for the other tank inhabitants.

It becomes much trickier when it comes to housing crayfish with fish. There are many accounts of people successfully keeping crayfish and fish together, but given enough time, either the fish or the crayfish is going to be eaten. There is nothing worse than losing a large, expensive fish to a crayfish over the course of a night. Or alternatively, finding crayfish parts scattered across an aquarium, with a very full looking fish. While a person can certainly try to keep fish and crayfish together, it ends badly more often than not.

The filtration for a crayfish should usually be a HOB (Hang-on-back) filter (You can find the Seymour Fish HOB filter reviews here). While a sponge filter is cheaper than an HOB filter, the air line leading out of the tank gives the crayfish a perfect escape route. If you leave the crayfish alone long enough, you will eventually see a crayfish running around on the floor of your fish room.

Feeding

A crayfish’s main diet should be comprised of sinking Shrimp Pellets, but they also enjoy some green vegetables and frozen foods in their diet. They are not picky when it comes to green vegetables and can be offered cabbage leafs, zucchini medallions and shelled peas. As for frozen foods, they happily accept small portions of frozen fish, daphnia, bloods worms and brine shrimp.

A word of warning – crayfish love aquatic plants and will eat any that are put in the tank with them. An adult crayfish can strip a heavily planted aquarium bare in a matter of days. So while it may be a good place to dispose of unwanted plant clippings, you should never put any plants in their aquarium that aren’t replaceable.

Breeding

Most species of crayfish will breed at any time in the home aquarium, though feeding high quality foods and keeping the water pristine will help trigger breeding behavior. Crayfish can be frustratingly hard to sex for someone new to keeping them, but the easiest way is to look at the swimmerets. The males will have swimmerets that extend past the back legs, while the females won’t have any past the back legs.

When mating begins, the male deposits a sack of sperm on the female who then passes her eggs through the sperm to fertilize them. After the eggs have been fertilized, they are then kept under the tail by the female who should be placed in a tank on her own at this point.

After around four weeks, the eggs will hatch and the young crayfish will emerge. The female crayfish will take care of the young for a short period of time, but should be removed after a few days to prevent the fry from being eaten. A large nursery tank is required if any number of crayfish fry are expected to survive as they are extremely cannibalistic like their parents.

The baby crayfish can be feed blanched cabbage leafs or lettuce leaves, and also consume detritus in the tank. As the crayfish grow, the larger ones should be removed from the tank as they will feed voraciously on the smaller crayfish.

Comments

  1. Mihajlo525 says

    Its not hard at all to sex crayfish!! Its sooo simple the male has large claws and a small tail while a female has small claws and a larger tail about the width of her body. And where the body and tail connect (under the crayfish) if there are little arms then its a male if there are no little arms there then its a female. See EASY. And when they mate the male will always be on top. And i find it a lot easier and cheaper to catch them.

  2. Ringo Roach says

    I live in Hawaii and put a crayfish in my 5 gallon tank with two long fin Rosy Barbs-all have gotton along well for the past month and a half. I noticed yesterday my crayfish is loaded with eggs. Could they be fertile? or just empty eggs? Mahalo

    • says

      Unfortunately most species of crayfish need a male to produce fertile eggs, so the eggs should be infertile. Do you know what species your crayfish is? It’s also amazing that it’s living peacefully with your fish. My electric blue crayfish and red crayfish both annihilated the fish I tried to keep with the years ago.

  3. says

    Procambarus clarkii I had a male and female, survivors of a crawfish boil. They mated. They were the perfect happily married crawfish couple! Poor girl died today during molting. I opened her up to check on things. She was full of eggs! Darn. Had she survived the molt, I’d likely have babies soon. So sad. I did notice her gills were not in the right place and part of her tail was not complete. Something happened. Poor male is in hiding. I think he knows his mate is gone. He was always so protective of her. He was even protective of her dead body. Threatened me like it was my fault! Sorry, dude. I won’t be able to get another female for him until after the first of the year. He’s old. Might not even make it til then.

    • says

      Do you have soft water where you are? I have pretty hard water where I am, but I noticed that after a while some of my crayfish started having problems moulting, and it cleared up when I started feeding them vegetables high in calcium.

      And mine don’t seem to understand that I’m larger than them – they always threaten me too.

      • says

        I feed mine shrimp for calcium and there are oyster shells in the tank that puts the calcium in the water. My water has a lot of natural calcium. So I don’t think it’s that. From what I’ve researched, sometimes there’s just no explanation.

          • says

            Sorry to hear that. Crayfish have such great personalities…you really miss them when they’re gone. Mine used to always escape (even with more and more insane efforts to keep him inside), and I’d always see a crayfish covered in dust bunnies running around my living room.

          • says

            I have a snap-on lid that crawfish can’t budge! I lost one several years ago after it managed to get out. Found it too late…covered in dust and dry. It must have been out of water all night and my guess is that the cat may have played with it. That guy was hilarious!

  4. Sara Richards says

    Hello fellow cray keepers, nice to find this site.
    I have quite a few crays – P.Alleni, P. Clarkii, CPO, & Painted Devils. I’ve never had an escapee, and they really don’t seem to try very hard. Other than the Painted Devils, most of them scavenge and feed underwater 90% of the time, sometimes when very hungry they climb up onto land more. I think because they can so easily leave water they will attempt to escape to new waters whenever the parameters are not to their liking, much like snails do.
    I do find many of them seem to like sitting on driftwood above water level directly under the flow from the HOB filter. They will sit under it for hours. I try to set up my tanks so everyone has that option, and always provide an area above the water for all of them- sometimes they just seem to want to come out and it may serve some important purpose. I disagree with the notion that they be kept in a 100% aquatic set-up.

    • says

      My P. Clarkii guy (the other died during molting) loves to sit on top of his house or on one of the large oyster shells I have in his tank. He has enough water to submerge himself. From what I’ve read of the habitats of Procambarus clarkii, they are quite diverse. They can live in mud, puddles, anything wet, even stagnant water. I agree with you about not having the full aquatic set up.

  5. says

    I’ve got 4 bunch of 3in-4in P. clarkii, 2 orange, 2 bue.

    Well, at first, it was just one blue. He actually was always hiding at daytime.

    However, when I added the others, they all seemed to walk more frequently. Nice little creatures!

    • says

      They really are great little features. They’re are overlooked by so many people, but if you add a few to a tank, you really get a lively and interesting tank. Good luck with your crayfish.

  6. Tom says

    I rescued a small crayfish while fishing a few months ago , he was in a fight with a larger crayfish , and losing badly , no claws , and 2 legs gone. he now has his legs and claws back , and is happily digging holes and moving every piece of gravel in the tank , although he has become a bit shy after challenging a Black Banded Leporinus to a fight.

    • says

      That’s great that the crayfish came back so well. It’s amazing what they can heal from, and they’re always fun to watch.

      I hope that your Banded Leporinus stays safe. I had a friend who recently lost a juvenile Arowana to a crayfish – he was not a happy camper.

  7. Uppie owner says

    We thought we had a male, but based on the large clutch of black eggs under her tail we were wrong :) Uppie was “rescued” from a University lab that was done with them and looking for homes. We’ve had a lot of adventures with her, but now we’re wondering what we should do with the eggs. Should we just leave them and clean them out of the tank as they fall out, or should we remove them altogether now (assuming she would let us of course – she’s a fighter)?

    • says

      Just leave them on the crayfish, and they will eventually die – or hatch. Some species of crayfish are all female, and others can carry sperm for up to a year, so the eggs might just be viable.

      And crayfish are a ton of fun. I’ve spent some time with my crayfish chasing it, or fighting with it so I can remove it’s enormous stash of food. lol

  8. Sara Richards says

    The eggs could still very well be fertile, the female can carry the sperm packet until she chooses to lay eggs. If she has molted since you had her then chances are they are not fertile since it is believed the sperm packet is shed along with the exoskeleton when a female molts. Still just leave them- she will enjoy the caviar. I find that female P.Alleni and P. Clarkii with fertile eggs tend to cave up and eat very little or not at all until they hatch.

  9. Jacob says

    I have a Virile (Northern) crawdad that I caught in my creek. Everywhere I look shrimp pellets are recommended as food, but there are no shrimp in my area. So what should i feed it? (so far I have been feeding it cat food)

    • says

      Cat food will work, but it can get messy. You can make your own food out of shrimp and feed it. That’s what I do for my fish sometimes. Just use non-oily fish, lots of shrimp, and then about 30% of the rest of the food should be peas, broccoli and zucchini. Once you have all that together, blend it up and allow it to set with gelatin. You can find more indepth recipes online, but it’s great if you really want to tailor your crayfish food. And you only need to do this once every month or so.

      If you don’t want to do that, just feed them a combination of sinking fish food, and vegetables every few days and they should be happy. The key is getting the food down to them.

    • Sara Richards says

      Hi Jacob,
      Shrimp pellets per say aren’t required. Any good sinking fish, turtle, or invertabrate food is fine. In fact, offering a variety is probably better, being crayfish are such opportunistic feeders. If your cray is an adult, more plant based foods (algae wafers, spirulina pellets, etc.) with some occasional protein (earthworm, bloodworms,fish) are good. Tiny babies probably eat more protein for their size in the form of bacteria and microorganisms containeded in the biofilm of decaying vegetation, but adults likely don’t get as much. That’s probably why animal protein (fish, live worms, etc.) type foods are such favorites, they are rare and prized finds in the wild. Leafy greens and mixed vegetables are always appreciated, keeping a small bag of frozen spinach and one of mixed veg on hand are a convenient way to provide those. Kernal corn is a favorite.
      One thing not often mentioned that I think is important is to also provide them with dead dry leaves, oak or similar. Every cray species I’ve kept, both adults and babies, eat them extensively regardless of how well supplied with other foods. I’m sure it’s the biofilm they are after to some degree, but they chew and eat the entire leaf so I imagine it’s an important element in their diet. I use Indian Almond leaves because I have fish as well. Dead leaves also make a great “vacation feeder” since a cray can live off them quite a while and they don’t foul the water, though they will tint it an amber color which is harmless.

      Good luck with your cray!

  10. Lee Polk says

    Wowl that’s some good information. I keep crays from time to time. I have three small ones currently and I keep them in a ten gallon with a couple mud minnows a baby bream and a few pot gut minnows. I had a baby channel cat but when my son caught the crays i released the cat fish back in our pond. I will put the two biggest crays in the pond this spring. Its a fairly large pong 160 feet by fifty feet. Oh I also have a elver (baby eel) in my tank..well I did unless a cray ate it..I find my crays love lil peices of beef jerky I chew to a pulp and drop it in. They all come out their caves for some jack links. Best part of all is they don’t mind I named each and every one I’ve ever owned…Edward Scissorhands

  11. Lee Polk says

    I put one of the big crays in the pond today. I just don’t want them to fight and it was terribly cold when my son brought them to me. Its so cool to watch them endlessly eating. Its like my dad said about me when I was a kid. “Every time your elbow bends your mouth flies oopen”
    I did see the elver swimming around yesterday evening . They don’t like the light but sometimes I see it when nothing but the television is own. Who knew eels were fans of watching Ancient Aliens?
    I wouldn’t worry too much about lack of creativaty in cray names…. mine never come when I call them.

  12. KC says

    Hello all im also a crayfish enthusiasts. Im looking for rare and/or color morph crayfish. Im specifically looking for Cambarus Ludovicianus aka Painted Devil crayfish. Please email me if you have any or anything I maybe interested in. I will pay. Thanks in advance. =)
    Beastlyadamzz@gmail.com

  13. Xavier Williamson says

    Thanks for the advice in your article but still have a lot of questions – I recently made a purchase of a “red lobster” – obviously really a crayfish to my freshwater tank. It just so happened that last week I noticed it was pregnant and purchased a smaller tank to isolate it. (took existing water and gravel from old tank to mature the new tank as quickly as possible). I now have at least 100 little guys running around the tank and have since put the mother back in the normal tank. Any advice on how to care for them? Feeding amount/frequencies? Lights on or off? Temperature? When do separate the larger ones etc? Any advice would be greatly appreciated as this was not planned but a fun project to work on.

    Thanks

    • says

      I’ve done a lot of experimenting since I wrote the article, and assuming your crayfish are the red lobsters I’m thinking of, I would do a few things to raise the babies. You should feed them small amounts several times a day, and most seem to actually feed more the critters that break down the decaying plant matter, or fish food than the actually food itself. I had great success adding alfalfa and other bits of vegetation that break down, and feed them.

      I also increase the temperature to summer levels in the tank, and like to keep it around 74 degrees plus. This has been trial and error, and since there is so little info on raising crayfish, I admit that I could be wrong. I do this based on the assumption that they are born during summer though, in relatively warm waters.

      I also found that when I keep too many of them together, there are many that are cannibalized or lose limbs. Keep the density as low as possible, and provide numerous hiding places. If you have a 10 gallon tank, I wouldn’t keep more than one per gallon. Of course this results in a lot of tanks, so normally I remove the largest to a grow out tank, and leave the rest.

      As for lighting, I haven’t noticed any difference in lit or dark tanks, though there is usually room lighting and natural light. You should be fine on a normal 8-12 hour light schedule, but this isn’t something that I have played around with as much.

      Hope this helps.

  14. Lee Polk says

    I still love to watch mine.I have two in a tank and the smaller female usually stays well clear of the male. Today I noticed them mating and got a couple pics. I will turn the big male into the pond as soon as its warmer. I hope she gives me a clucth of critters. I have pleanty of pond area swampy and shallow that the bass can’t get to them as they get bigger.

    • says

      That’s cool that you captured some pics of them mating. I always try to get some of mine, but I always seem to just miss it. And to this day, they still are the most entertaining pet that I have in my house (aside from my dog.)

  15. Ari says

    Great info! Maybe you can help me. Doing this research has been frustrating because I consistently find contradictory information, sometimes even on the same site. I have one, approximately 4″, electric blue crayfish. I have had her since November and she has moulted once in that time. I thought, and still do, that she was getting ready to moult again because she has been hiding and not eating. I shined my flashlight into her cave to check on her and discovered that she is carrying eggs under her tail. I know they can store sperm for some time and it is possible they could be fertile but I don’t know how to tell? They are light pink in color. Some sites say that she would not have laid them if they were not fertile and others say that because she has moulted since mating they will not be fertile. Everyone says that darker eggs are more likely to be viable but no one can tell me if my light pink eggs are fertile or not. Can you?

    Also, I still think she is getting ready to moult as it is about time and her tail is discolored, a brownish rust color. What is going to happen to the eggs, fertile or not, when she sheds that exoskeleton?

    Any help would be greatly appreciated!

    Thank you

    • says

      Hello,

      Sorry about the delay in getting back, but generally pink eggs indicate that the eggs are not fertilized. Although it should be said, that I have no experience breeding the electric blue ones, and I’m just going by the other species of crayfish that I have kept. Also, from what I have read if the eggs are fertilized the female will delay her moult, though once again, I only know this definitively for cold water crayfish.

      Hope this helps.

  16. pinetree says

    I posted earlier about the same thing. The eggs ended up being washed away when I changed the water, and I’m assuming she ate some of them. None of them hatched. It probably took about a week before they were all gone and she straightened out her tail.

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