Can you tell me what kind of Crayfish I have? 6/21/11
Last week, on Thursday, my husband mentioned something about a tower by the porch. He, points to the ground by the back porch. There is a tower of Mud that stands about 10 in tall with a hole in the middle. He said, I'm watching to see what comes out. We figured a mole, or some kind of frog.
Friday we had a hard rain, and it washed away some of the tower, so he is standing there watching to see what comes up. It started coming to the top to rebuild the tower. When he saw what it was he knock over the tower and put what came out in the fish tank (it didn't have any fish anyway).
I know it is a Crawfish but not what kind. (I believe it is a male). We live in Eastern Alabama middle of the state 10 miles from the Chattahoochee River that separates GA and AL. We had a creek that went through our back yard, it finally went underground about 17 years ago. I have attached two pictures of it.
About 7 years ago, we had been doing some digging in the back yard and came upon some old rusty barrels, they were full of water and it had a bunch of little ones in it, we caught 2 little ones and one big one (not as big as this one). But they only lived six months. I think the big one ate the little ones (along with the rest of my fish). The big one also kept escaping the tank.
With this one, we have removed all the fake plants and moved the two fixtures that are left to the middle of the tank. And taped over all the openings. It has a filter and heater, with gravel on the bottom. I gave it a piece of cooked shrimp and put in flake food. It has not eaten the shrimp. I would like to know what kind it is and I have been reading your site for feeding tips. Won't lettuce float? And should I just cut up small pieces of carrots and zucchini? How much do you feed them?
Thanks for your help.
Michelle
<Hello Michelle. At first I thought this was Procambarus pygmaeus on account of its small size and the orangey tips to the pincers. But I do wonder if it is actually the common species Procambarus clarkii. In any case, I'm fairly sure it's a Procambarus species of some sort. As for care, do read here:
http://www.wetwebmedia.com/ca/volume_5/volume_5_3/crayfish_basics.htm
http://www.wetwebmedia.com/ca/volume_1/cav1i4/crayfish/crayfish.htm
Basic care is generally straightforward. Crayfish eat both plant and animal foods and under aquarium conditions are very omnivorous. Algae wafers, cooked peas, small bits of fish fillet, unshelled shrimps all make good foods. Variety is important. Dose the tank with iodine (sold for marine aquaria) at 50% the dose stated on the bottle -- this is very cheap to do, and ensures they moult properly. They tend to be aggressive as well as predatory, so will harm one another as well as fish. They like to dig, and yes, they will escape given the chance. Hope this helps, Neale.>

Re: Can you tell me what kind of Crayfish I have? Sys., nutr. 6/21/11
Thank you Neale! The information on what and how much to feed it wonderful. The algae tables are not as big as a penny and the seem to dissolve in about 5 minutes.
Did I get the wrong thing?
<Sounds like it. Use these for now; if the substrate is sandy rather than gravel, the crayfish will "sift" the sand and extract the nutrients.
Smooth, non-calcareous sand, like pool sand, is ideal for crayfish tanks. The best algae wafers for crayfish are the sort sold for Plecs, for example, Hikari Tropical Algae Wafers. These take hours to fall apart. A German company called JBL also make a whole range of foods expressly formulated for freshwater crustaceans.
http://www.jbl.de/en/aquatics-freshwater-products/group/2780/crabs--shrimps
Although pricey, like most German products, they're excellent. A pot used to supplement the foods outlined earlier would be an excellent approach, and economical too.>
Thanks,
Michelle
Re: Can you tell me what kind of Crayfish I have? 6/21/11
Neale, it has gravel not sand.
<Acceptable, but less fun, and I'd argue less easy to keep clean -- dirt sits on sand and can be pipetted out with a turkey baster (a great tool for the aquarist!). Gravel has gaps that let dirt sink down, so while it
*seems* cleaner, it's not.>
Where is the best place to get the sand?
<In the US, pool sand seems to be the easiest and cheapest option. Here in England, I tend to buy something called smooth silica sand (also called smooth silver sand as opposed to sharp sand) that is widely sold in garden centres. In either case, the stuff is very cheap.>
Do they have it at a pet shop?
<Some pet shops have non-calcareous sand (as opposed to the coral sand used in marine tanks). But they usually charge several times what garden centres charge.>
And I know I sound stupid but what is a "Pot" you mentioned to supplement the diet?
<Pot, as in a container. I meant you could buy one container of fancy-pants JBL food, and use it to supplement the kitchen and frozen foods.>
Michelle
<Cheers, Neale.>
Re: Can you tell me what kind of Crayfish I have? 6/21/11
Thank you for the information. You were most helpful and patient with me
for stupid questions. Have a great day.
Michelle
<Glad to help. Cheers, Neale.>

Crayfish Identification 3/19/11
Hi,
<Salve,>
I recently bought two crayfish from Petco that were labeled as "Vanilla Lobster" and "Asian Blue Shrimp." Both look exactly identical except the Vanilla Lobster is completely white and the Asian Blue Shrimp is, well, blue (but not a dark hue like that of and Electric Blue).
<These are rather odd. >
I live in WA and LFS label crayfish as lobsters and shrimp to get around a law preventing the selling of crayfish as they are an invasive species and people release their pets into the wild regardless of how wrong it is.
<Indeed. In the UK, the only crayfish that is routinely and legally sold as an aquarium pet is Cherax quadricarinatus, a tropical species from Australia that cannot survive in UK waters. Unfortunately, for you, there are other Cherax species from Asia and New Guinea that share the same blue colouration, such as Cherax sp. "Blue Moon" and Cherax destructor. On top of that, some of the North American Procambarus species occur in blue morphs as well, including Procambarus clarkii "blue" and the standard form of Procambarus alleni. Incidentally, Procambarus clarkii is also available in a white morph, Procambarus clarkii "white". Some of the larger fan shrimps can be mistaken for crayfish, most notably Atyopsis gabonensis, but I don't think that's the issue here. Similarly, big Macrobrachium species do turn up in the trade, notoriously the giant species Macrobrachium rosenbergii, but these are so distinct in terms of the length of their arms that they're unlikely to be confused with crayfish, despite the same blue colouration.>
I was wondering if you could please help me identify what species of crayfish they are.
<Not really; but if Google some of the Latin names I've given you, and visit the better crayfish sites like http://www.crusta10.de (you'll need to be able to read German to make much headway there) and compare my suggestions to what you have, you might be able to pin things down yourself. Cherax species shouldn't be viewed as "bad" in the sense of being pests in your part of the US, because they're all warm-climate animals with minimal tolerance for freezing conditions in winter. But further south in the US they may be less welcome, and on the whole, the very limited usefulness of crayfish doesn't (in my opinion) offset their potential for causing harm. Since you CANNOT keep non-dwarf crayfish safely alongside other fish -- they're ALL opportunistic predators to some degree -- they're really of interest only to those very few aquarists willing to set up a crayfish-only system.>
I have enclosed pictures to hopefully help. The picture of the Blue Crayfish is not a picture of my specimen (mine was avoiding my camera at all costs) but of one that is identical.
Thank you for your time and effort.
Ryan
P.S. Sorry about the two pictures of my white crayfish being so large. I don't know how to make them smaller.
<On the Macintosh at least, use the default image viewer, Preview, choose "Adjust Size" from the Tools menu, and then use the pull-down Fit Into'¦ option to choose a useful size, say, 640 x 480. Then choose "Save As'¦" from the File menu, and save the resized photo where you want it. Easy as pie! I assume there's something broadly similar on Windows. Cheers, Neale.>

Can you identify, please? 3/15/11
Hi,
I have found lots if great info on your site, and was hoping you can tell me what species my lobster/crawfish (not sure) is?
Thanks!
Elaine
<Looks like the Electric Blue "Lobster" to me, Procambarus alleni. It is in fact a crayfish, despite the name. Doesn't do well at tropical temperatures, usually succumbing to a bacterial or fungal infection; keep
at room temperature instead. This species is primarily a scavenger that consumes a good mix of plant foods alongside carrion, but under aquarium conditions will attack fish and shrimps during the night -- do not mix with fish or other tankmates! Dose the tank with iodine as per marine aquarium requirements, but at 50% the dose stated on the bottle. Without iodine these crayfish often fail to moult reliably. Cheers, Neale.>

Re: Can you identify, please? Crawdaddy, now incomp. 3/16/11
Thanks; I suspected he was an electric blue. I do add iodine, started adding shortly after discovering your site, just after I acquired the crayfish.
<Excellent.>
Just to let you know my experience with him - I got him when he was just under 2" (he's molted once that I know of, its been a few months that I have had him), & added him to my community fish tank. I have a mix of guppies, platys, tetras, Danios, & mollies; 'Krusty' and the fish seem to get along well - the platys actually hang out in his cave with him, and he doesn't seem to mind them visiting.
<Cool. But don't trust him completely! Any signs of physical damage, especially to the slow-moving Guppies, and whip him out. Yes, these animals are largely herbivorous in the wild, but they will catch small fish given the chance.>
I do make sure I drop food at the entrance to or just inside his cave, as the fish tend to not leave much for him otherwise. He cruises the tank at night, sometimes in the morning as well, provided I leave the light off.
<Indeed, they are very nocturnal.>
All that being said, I don't think I would recommend anyone add one to their fish tank, unless its a large enough space with sufficient shelter and cover (I have lots of live & plastic plants, so even when not in his cave my crayfish has plenty of hiding places).
<Are indeed fascinating pets, but on the whole, best kept in their own tank. Cheers, Neale.>