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Crayfish, Crawdads, Yabbies, Ditch Bugs Disease Treatments

FAQs on Crayfish Disease: Crayfish Disease 1, Crayfish Health 2, Crayfish Health 3, Crayfish Health 4, Crayfish Health 5, Crayfish Health ,
FAQs on Crayfish Disease by Category: Diagnosis, Environmental, Nutritional, Trauma, Infectious, Parasitic, Social,

Related Articles: Forget Crawfish Pie, Let's Make a Crawfish Tank! By Gage Harford, Invertebrates for Freshwater Aquariums by Neale Monks, Freshwater Shrimp, Crayfish, "Lobsters", Prawns Freshwater to Brackish Crabs

Related FAQs: Crayfish 1, Crayfish 2, Crayfish ID, Crayfish Behavior, Crayfish Compatibility, Crayfish Selection, Crayfish Systems, Crayfish Feeding, Crayfish Reproduction, Freshwater Invertebrates/Use in Aquariums, Freshwater Crustaceans for the Aquarium, FW Crustaceans 2, Fresh to Brackish Water Crabs, Hermit Crabs,

 

Crayfish - change in behavior after change of aquarium and molt     12/4/14
Dear WWM Crew, My husband and I live in Japan and about a month ago we bought a couple of crayfish,
<Oh! I kept these as a youth there as well (Dad was a lifer in the Nav)>
which are very common in pet shops here. By Googling and checking pictures we believe we have Procambarus clarkii but we might be mistaken,
<This one species of Cray has been transplanted by humans most everywhere>
they were not very specific in the shop. We got a white one and an orange one. I have read your articles and FAQ but we are still wondering about a change in behavior in one of our crayfish. They told us since they were roughly the same size they could live in the same aquarium,
<Mmm... until one molts and the other is hungry... DO keep your eye on them, DO provide a one-way in only (like a blind piece of PVC... pipe and cap) and KEEP them fed (daily)>

and in the shop they were kept in the same box. So we set up a 60L tank with plenty of hiding places and few plants that we were told they enjoy eating, plus filter and heater set to 23°C (there is no such thing as central heating in Japan and our rooms can get very cold during winter)
<S/b fine for these animals>
. We bought them the specialized pellets they sell for this type of crayfish and started our adventure. After few days they seemed to be doing good, <well> and showed distinct personalities, the white one despite being the one who got most easily scared by our presence would stay in the open while eating, while the orange one would come to the glass and show his bravery whenever we approached, but would carry away his pellets and feed only while hiding inside a cave. Perhaps a week after we got them I caught them by chance in the middle of a fierce fight and in the next couple of days the white guy started “mysteriously” loosing <losing> limbs. So we decided to separate them, at least for the time being as clearly the white guy was no match in his state. The decision was even more pressured as white guy molted and we knew he would be too soft and could get killed.
<Too likely so>
We transferred orange fellow to a smaller tank with similar setting.
<Good>
This was three weeks ago. White guy has since molted again,
<... some deficiency at play here... What is the hardness of the water? Do you measure pH... ? What water source are you using? Are you administering iodine (ide-ate actually)?>
his legs growing very fast and himself growing quite a lot. We are surprised by such fast molting and hope it is normal.
<Not normal, nor healthy>
I have more or less come to understand his routine, he stops feeding for a while, he molts and after a couple of day she has finished eating his exoskeleton and is back to his normal antics, eating his pellets as usual. Orange guy on the other hand, has us very worried now. For the first two weeks he behaved as he had in the big tank, playful and showing himself when we approached, but hiding to eat and sleep. On Monday evening we discovered he had molted when we returned from a weekend trip. It's been 4 days since we found him and he has eaten only about half of his exoskeleton and has refused any extra food we tried to give him, he stays in his cave and rarely comes out all. Is this behavior part of his normal routine after molt?
<Again; something is off, missing here... see the terms above in the archives on Crays on WWM>
Just as he has behaved different from white guy, he acts different in this case too? How long should we wait for him get back to normal? We are worried he needs something else,
<Yes>
which we are missing from his small tank compared to the fellow in the big tank. He has less space and hiding places, fewer plants, which he barely eats anyway as opposed to white who constantly nibbles on them, and different rocks at the bottom. Everything else we have tried to keep exactly the same. Any advice or recommendation would be very helpful. I attach a picture of how we found him four days ago after we came back, in case it helps identify him and if something is wrong. We have since cleaned all the uneaten food that you see in the picture, and changed25% of his water. Thank you very much, Camilla
<The I2 will likely work wonders... Can be purchased for aquarium use... Check your water quality otherwise. Perhaps your water is "too soft", lacks Ca, Mg salts, carbonate. Bob Fenner>

Blue Crayfish lying on side and not eating    2/8/14
Dear WetWebMedia
<David,>
I have searched for days all over your website and others but find a few possibilities on what the "problem" might be. Could you assist?
<Possibly, but crustaceans tend to exist in a binary state so far as healthcare goes: they're either fine or dying. That's because we have virtually no understanding of how to use medicines to help them. The one exception here is Iodine, which can be a "silver bullet" in some situations, specifically prevention of moulting-related problems. Other than that, about all you can do is optimise the environment and hope the crustacean pulls through under its own steam. Many do.>
I am from the UK and I have had a Blue Crayfish for around six months now.
"His" name is Baldrick (he says hello).
<Hello.>
Lately Baldrick has been lying down, intentionally, not falling or getting pushed over by anything on his side which is what prompted my search.
<I see.>
A bit of history: He was extremely active as a "baby". He would jet around the water, dig, wreck and climb the plastic plants. All sorts.
<Sounds normal so far.>
As he got bigger he did less but I figured that was natural. He hasn't shed for quite some time - I think two-three months now whereby before it was monthly.
<Again, not unusual; as crayfish age, moulting becomes less frequent, and eventually may stop altogether if the crayfish is very old.>
I always left the shells in there as he seemed to like eating them.
<Correct analysis; recycling the calcium. Not essential you do this (old moults are a way for crustaceans to get rid of heavy metal poisons like copper, for example) but crayfish should certainly have some source of calcium available to them, whether a moult or something like a unshelled prawn to eat instead.>
He would go through his normal cleaning cycles but lately, the last few days I've noticed he is almost constantly cleaning himself, almost violently (before it would be the occasional big clean and maybe just a little rub here and there). He is almost always jamming his back legs where the swimmerets are. I thought there might be a problem or eggs (some how) but it looks normal under there.
<He may be having a problem moulting; do you use Iodine?>

Today he was really having a go around his eyes and opened his face (like something out of predator) up for a "full" clean - I'd never seen that before. Lately he quite often will tuck his tail underneath himself and scuttle around as if he is about to be eaten, then lay down on his side and not move for a little while. I thought he was dead until I tested him by dropping a bit of food in there. He jumped up in his usual way and scoffed the food instantly. However, the last two days he's barely eaten. He responds to fresh food as always - but only eats maybe one pellet. He brings other pellets to his mouth, tries them and then drops them which is very out of character for him. I have food two days old just sitting on the bottom of the tank - he is completely disinterested. When you think it's all doom and gloom and he is about to die, he will untuck his tail for around 10 minutes and wander around without any problems - however the feeding hasn't rectified.
<If you don't use Iodine, do so; you can inexpensively buy Iodine supplements for marine aquaria, and dosing at one-half the amount quoted on the bottle will be ample. Iodine is essential for proper and regular moulting, but unless we offer crayfish Iodine-rich foods (primarily seaweed like Sushi Nori as well as certain seafoods) they often are starved of Iodine. Without the Iodine the moulting process sometimes "jams", and crayfish can find themselves in all sorts of trouble. Using Iodine is a quick, cheap fix (and preventative) to these problems.>
He is alone in a large tank. I have changed about 40% of the water and cleaned the glass - no effect.
Thanks in advance
Yours
David
<Hope this helps, Neale.>

Iodine for Florida Blues   1/29/13
Hello. Sorry for bothering you people with so many questions regarding my Florida Electric Blue Crayfish! But they are my boys, and I want them to live in the best possible condition! An update: Orion, the egg carrier who lost a claw due to aggression from the large alpha Boris, now I know the reason for the aggression. Boris, a few days later, was also carrying eggs, the same day I found that Godfather was hiding so much in his tower because he, too, was carrying a large batch of eggs!! So I will have my hands (and tanks) full in about 2 to 3 weeks, when I find the hatchlings. I am already preparing a good environment for the hatchlings, hoping to grow at least a few young crayfish from the 3 batches of eggs. I'm glad that the three Crays lay eggs approximately the same time, so the hatchlings should be ok, if they're the same size and have a lot of hiding places, to avoid too much cannibalism which I know is unavoidable.
<Indeed.>
My first question: When I place my hatchlings in their temporary home, what is the best material for the bottom of the aquarium?
<Best: nothing at all but bare glass. Easiest to clean, and the silt and detritus is the stuff that promotes fungus on eggs and bacterial infections on very young livestock. If plain glass doesn't suit, then something easy to clean would be fine. A very thin (1-2 mm) bed of soft silica ("pool filter") sand for example or very fine pea gravel.>
I don't trust the sources I have read from. One said that soil/peat moss, preferably from a local pond, with some dead leaves is the best for hatchlings. I think this is a terrible suggestion, mixing outside materials into an aquarium of hatchlings. Another suggestion was leaving the bottom of the aquarium empty till the young Cray are about an inch in size. Is this appropriate, having nothing for the little guys to walk around and dig in?
<Is fine.>
Another said aquarium sand. This seems more believable, but with the frequent water changes required, I'm unsure of how the sand could be kept clean of uneaten food and Cray feces.
<If very thin, as stated above, there won't be any anaerobic decay (you need a few cm for that to happen). In any case, faeces tend to sit on top of sand, rather than sink into the gaps between gravel particles.>
Would the coral/gravel mix I use in both of my crayfish tanks be find for the hatchlings as long as they have a lot of plants and hideouts?
<Yes.>
My second question is the use of Iodine. I went to four different LFS and none of them had any idea or knew about any form of iodine/iodate salt for use in aquariums. All of them sent me to the pharmacy to pick up Iodine Tincture BP 2.5% (25ml bottle) with a mix of Iodine 25mg/ml and Potassium Iodide 25mg/ml, with non medical ingredients of Ethyl Alcohol and Purified Water.
<Doesn't sound safe.>
Without thinking much about it, I put 3 tiny drops in some water from the aquarium and mixed it into my 10 gallon, and 5 diluted drops into my 20 gallon. Only now am I in fear that my Crays, Zebra Danios, Yoyo Botias, and two young Gyrinocheilus Aymonieri in terrible toxic danger!! Two hours have passed since the iodine drops, all the creatures are acting normal, no red gills or panicked stress, Crays are fine too. Is it possible that they will all survive my ignorant toxication of the aquariums? Please help me, I am afraid of what I will find in the morning, whether there will still be life in my tanks!
<Iodine is readily removed by carbon, so you could always choose that. In any case, if the animals are fine a few days later, they're probably haven't been harmed.>
If anything happens to my beloved aquarium friends, I will have some visits to the four LFS to do, and some strangling and beatings to hand out to those "fish experts" and myself for being stupid enough to buy and add the pharmacy Iodine to my Aquariums.
<You're looking for products such as Salifert Natural Iodine, Kent Marine Iodide, Seachem Reef Iodide, etc. Typically inexpensive products, $5-10 a bottle, and you can use them at half the dose stated on the bottle.>
Thank you, as always, to your time and support, and priceless help and advice!!
Much appreciated. ~Sylvia
<Glad to help, Neale.>

Blue, the blue lobster/crawfish    6/23/12
Hello, I just have a inquiry about behaviour. 2 weeks ago, I picked up what was titled a blue lobster.
<In the US at least, almost certainly the blue version of the standard crayfish species Procambarus clarkii, the species farmed and eaten across North America and elsewhere.>
Massive sale 85% off the regular price. He was about 1 inch long and later I noticed he was missing about 60% of his legs (rough guess).
<Like all members of the Decapoda, crayfish have ten legs, i.e., the two pincers and eight walking legs. There are other appendages to be sure, but these are specialised in other ways, such as the swimmerets on the abdomen.
So, if he has 60% of the original ten legs (including the pincers) he's down to just 4 legs (including the pincers). Does this help?>
Currently I am setting up his own tank that should be fully cycled end of this week ( I tend to cycle my tanks for at least 3 weeks before adding anything I want to keep, with a few fish I would other fish feed to betas or a fish I have yet to identify) Blue is currently sitting in a breeding basket with a house and a plant and a baby molly. This tank every thing is in the right range, pH is a little high for Blue (7.9) as this is my live bearing tank.  He just went through a molt.
<Good. Now, be aware the first moult is the easy one. It's the subsequent ones where things go wrong.>
He did not really get any bigger (most likely as he re-grew most of the missing limbs)
<Could well be.>
That being said. I was expecting him to hide in his house. He is not. He is wandering about following the baby molly out in the open. My question is, as this is generally abnormal behaviour after a molt, do I need to be worried?
<Nope, don't worry.>
Or is he just a strange little critter? He has been in the breeding box for 2 weeks now, could be he knows its safe?
<He doesn't "know" anything. But crayfish are opportunistic scavengers, and by their very nature explore their territories and try to either [a] eat or [b] swim away from anything else they bump into. It's a simple life!
Needless to say, both live plants and small fish are dinner items, sooner or later.>
Oh he does get lots of different foods, shrimp, blood worms, flakes, shrimp pellets, spinach, algae wafers, to name a few, and I add the reef iodine as well.
<Ah good. That's the key. Green foods, calcium and doses of iodine. Meaty foods are treats, once or twice a week, compared to the importance of greens and unshelled prey animals (krill for example).>
Thank you
<Most welcome, Neale.>

albino snow crayfish     6/19/12
I have a albino snow crayfish in a freshwater tank. I have had him sometime and he has molted a couple of times but hasn't for a while now. I changed the water and cleaned the tank like I usually do and added all the tank care chemicals I always use. But for some this time he is acting weird walking around with his tail curled under him. Won't eat the food he usually loves and doesn't stay in his usual hiding spot. Should I be concerned?
<I would be, yes. Do check the basics. Is the water temperature right for the species? The usual Snow Crayfish of the hobby is an artificial form of Procambarus clarkii, a species best kept at room temperature (around 18 C is ideal). Although not fussy about water chemistry, soft and acidic water is best avoided, so you're aiming for about 10+ degrees dH, pH 7-8. They are herbivores with a strong taste for carrion, so a diet based around algae wafers and green foods (cooked peas, blanched lettuce, spinach) will provide the main nutrients while occasional crushed snails, unshelled shrimps and whole lancefish (i.e., food with shells or bones in them) provide the extra protein and calcium they need to grow. All Crayfish benefit from additional iodine, which you can buy in marine aquarium shops for use in reef tanks. Add at one-half the dosage recommended and you should find your Crayfish is healthier and moults successfully. Last but not least, remember about their intolerance for many "medicines" such as copper and formalin. Many of these can be lethal to Crayfish, and copper can also be present in tap water, so remember to use a water conditioner that neutralises copper.>
Thank you!
<Cheers, Neale.>

Crayfish Problem 2/7/12
I have searched through most of the pages of the site and find no common problem or cure to my crayfish. He has been turning worse and worse since about 2 months ago, at the start at which he had only a little cracked darkened part on his antennas. Now today when I got home, he has all these white flakes on him that was not there a day ago. I have used some testing kits for testing the GH and KH of the water and try to lower these factors to 5 "dKH
<How are/will you do this?>
as well because I noticed both were relatively high at 10 "dKH GH and 10 "dKH KH. I have a 20 gallon tank with no plants and just one crayfish in it. Temperature is room temperature about 79"F and nitrate, nitrite, and ammonia is all low,
<Low? There should be no, 0.0 ammonia or nitrite, and less than 20 ppm. of NO3>
so I assume it is my hardness and alkalinity of the water that is affecting my crayfish.
<Maybe... along w/ sufficient nutrient... Do you utilize an iodide/ate supplement? You should be. Read here:
http://www.wetwebmedia.com/FWSubWebIndex/crayfishdisfaq.htm
and the linked files above; particularly Feeding FAQs>
I have noticed in the beginning when he looks sick it was plainly just the crack on his antennas, then the tips of his claws start turning blackish, now his body is full of white/brown flakes and he is sitting really awkwardly while the aquarium light is on for 6 hours a day and he is standing out of his hideouts. I feed him sinking pellets and once in a while beans and baby carrots but he doesn't like those and it molds in like a few hours. Before I give him plants the water would not make the sinking pellets mold in a few hours but now, everything I put into the tank molds really quickly and he is too sick to touch food now. I have been visiting the pet shop to check for solution to my problems and he told me to try to lower the GH with water changes and I have a bottle of tropical extract water conditioner to lower the KH from alkaline to neutral.
<I would not use this. Your GH and KH are fine as is>
Could it be because the acid water conditioner is too strong for him to handle? I have only used it once. And also I was talking with the pet shop's staff to know if my freshwater crayfish is suitable for iodine because that shop sells electric blue crayfish and orange crayfish as well, and he said he is not sure but its more common used for saltwater crustaceans, and not so much for a freshwater crustacean.
<Incorrect. Read where you've been referred; or search on WWM for iodide/ate and Crayfish>
Thanks for your time,
William.
<Certainly welcome. Bob Fenner>

Crayfish, death... from? - 8/10/10
I didn't see anything that matched what I'm wondering. If there is I'm sorry. I've had my crayfish for about 4 months. And it has molted once. And about 5 days ago it stopped eating and went into hiding. I thought it was molting again but this morning, I found it laying on it side dead in the middle of the tank. Do u know how this may have happen? I feed it shrimp pellets, And change its water often, has a good filter that filters for 10 more gallons of water than is in the tank.
<Hello. It's reasonably well established now that crayfish need the use of iodine in the water. Buy the stuff used in marine tanks as a supplement, but use at about 50% the quoted dose. If used regularly as instructed on the package you should find crayfish moult successfully and live healthy lives. Cheers, Neale.>

Electric blue crayfish, hlth., moulting, I2 5/12/09
Hello I have a question about giving my crayfish Iodine. I just bought some iodine for my crayfish and it says for every 50 gallons use one drop. I have a 20 gallon with 2 crayfish in it will this harm them from being to much
<There is such a thing as overdosing of this halogen... but there is a rather large range of efficacy... given the types of common interaction with many "tap"/source waters... and biomass... You will not have a problem with only administering the one drop... per... interval of when you do regular water changes (likely no more frequently than weekly)>
Or will my carbon and poly filter suck most of it out?
<Yes it will, would...>
Should I leave the carbon an poly filter out when I do put the iodine in?
<Yes I would>
If I do how long should I leave them out?
<A day>
I have been feeding them beef heart, algae wafers, tropical flakes, and a pellet for carnivores such as the red tailed cat. Is this food ok or is there something else that is better?
<These are fine... the beef heart can be messy though>
They have molted twice in my tank the first time was perfect the second is what has me worried. One of them is still a light pink and a bit soft still and it has been 4 days.
<I'd be reading, testing for alkalinity, perhaps biomineral (Ca, Mg) content in your water... maybe adjusting/supplementing for such if these are deficient. Please read here re: http://wetwebmedia.com/FWSubWebIndex/crayfishdisfaq.htm
and elsewhere (use the search tool) on WWM re the chemicals, properties listed>
So the iodine is the only thing I can think of to help her. Please and thank you for your help.
Deanna
<Mmm, w/o the water conditions noted, moults can be seriously hindered as well... Some folks have water that is too soft, otherwise lacking in alkaline earth materials, to successfully keep Crayfish. Bob Fenner>

Sick crayfish 9/11/08
Hello
I have a six month old blue crayfish. He has been in perfect health up until now. I found him 2 days ago missing an eye and with a large hole in his skull where it had been. His skull itself looks odd, it has 2 pointy things sticking out of it on either side near the eye sockets. He is on his own in the tank so hasn't been fighting. Please help!!
Amy
<Hello Amy. Crayfish are prone to problems when they moult. The key issue is some sort of nutrient deficiency, probably caused by the tendency for aquarists to give them a meaty or high protein diet rather than what Crayfish should be eating: plants and algae! In theory, your Crayfish can put himself together again with successive moults, so all in not lost. But adding Iodine to the aquarium will be essential (and inexpensive). This iodine is sold as a supplement for marine aquaria, but works fine in freshwater tanks. Do read this section of Crayfish diet:
http://www.wetwebmedia.com/FWSubWebIndex/crayfishfdgfaq.htm
There's a link on that page to a very useful PDF at the web site of JBL. Worth keeping to hand.
Cheers, Neale.>

Confused about Iodine for my freshwater yabbies - 02/11/2007 Hi again. Since last emailing we've had more Yabby deaths however we have learned a lot in the process so I'm confident our remaining three yabbies are going to do ok. <Ah, good> We ended up having to put our smaller male (Homer) in with our only surviving female (Mindy) in the larger tank (14 gallons). Our larger male is VERY aggressive so now has been named Hannibal by my husband (due to his fondness of eating his tank mates) <Heeee! Give that Carthaginian some grief relief... he only used to put spears through the feet of bearers of ill messages...> and put into the 5+ gallon tank on his own. All yabbies seem rather happy with the arrangement. I've been buying bits and pieces here and there and I think I now have the maintenance sorted and both tanks look really good. <Very good> I read in your FAQs that iodine would be a beneficial additive to their water. None of the aquarium suppliers in my area sell any. <Mmm, you can easily use "human" sources for such...> Although one remembered they did stock it once but phased it out due to little or no demand. I finally found some at an Australian online aquarium supplier so have bought that. I'm not sure how to tell if it is the right stuff though (is there a wrong stuff?) so I thought I'd come here and ask. It is called Success Iodine made by Red Sea, the label reading 'Iodine replenished essential for soft corals and invertebrates'. It says nothing about ingredients other that 'contains potassium Iodide'. Its dosage recommendations for reef and marine tanks is 5 ml for each 120 liters (31 gals). So my questions are... is this the right stuff? And, if it is the right stuff, is one drop per 10 gallons, once a week, still the dosage to use in my freshwater tanks? <Is fine to use... and this dosage, interval is fine as well> Many thanks for taking the time to answer this. The differences between our countries and various companies producing these products can make this kind of thing so confusing. I've been able to find no Australian information regarding this at all. Kind regards Tascha Marshall NSW, Australia <Happy to assist you. Bob Fenner>
Re: Confused about Iodine for my freshwater yabbies. 2/12/07
I swear my yabbies know when I email you and conspire to make me eat my words. <Heeee!> I thought I had it all under control but now my females behaviour is concerning me. I'm not sure if she is injured or producing eggs or what is going on. Help??! We keep finding her on her side in cozy hiding places. A couple of times we thought she was dead only to have her move away when we've got too close. I've also noticed her tail is curled under, which I know is not usually a good sign. <Mmm...> I haven't seen her eat, but then again I can't claim to have seen her eat before this. She tends to wait until no one is about before going out and finding her food. <Most such crustaceans are predaceous on each other... the smaller ones often eaten by their larger kin...> Just now I noticed her on her side again with what looks like a blue coloured bubble coming out from the side of her tail. I didn't notice it until I tapped the glass (I'm a slow learner.. I thought she was dead again) and she moved, and the bubble disappeared under her tail. Has she mated and produced eggs (I can't find pictures online of what they ought to look like) or has she some kind of injury? <Perhaps the latter... maybe developmental> Thanks for any help you can offer me. Kind regards A totally confused Tascha Marshall Aus. <You do have sufficient alkalinity and biomineral present I hope... some very soft waters need supplementation to keep these animals. Bob Fenner>

Crayfish Concerns, Medication - 01/23/2007 I've been scouring the internet and asking local fish store owners how I might treat my blue fresh water lobster. I noticed two weeks ago it wasn't eating and has some sort of growths on its large pincers and now it's developing around its mouth. Looks like fuzzy semi transparent growths. I've been changing the water on a regular basis but admit I was behind on this right before he became ill.... and I know they are very sensitive to water conditions. <What are your ammonia, nitrite, and nitrate readings on this tank? How big is the tank? How big is the crayfish? What else is living with it?> I don't have a clue how to treat something with an exoskeleton like this. <The typical rule of thumb is "don't". Currently, there is very little known about diseases and treatments of freshwater invertebrates. Adding medications to water with invertebrates is asking for trouble. Unless the animal is going to die otherwise, it's best not to play with medications and inverts.> Is it bacterial? fungal? <Without a much more detailed description and preferably an image, I do not know. I can tell you some Males of some Macrobrachium species shrimps develop fluffy growths on their claws naturally; it looks like "fur" of a sort, and may be part of attracting a mate. Algae can grow on the carapace of a crayfish or shrimp; though this is not desirable, it's usually harmless. My point here is that, since you have no idea what it is as yet, medicating is a bad idea.> I've tried PimaFix, MelaFix and it didn't seem to help. <In my opinion, these are worthless, and may even be harmful to invertebrates.> Now using Rally (Acriflavine) for two days and waiting till tomorrow to see if it is working. <This may prove fatal to your crayfish - medicating a crayfish is risky business at best. If the animal seems no worse for wear tomorrow, you might consider continuing with this, but if it were me, I wouldn't. I can't tell you for certain that it will be harmful to him, but I can also tell you were it me/my pet, I wouldn't be risking it.> Any ideas what it is and if there is a better treatment that won't kill it? <Pristine water quality, iodine supplements (if you're not using iodine, maybe now is a good time to start - I use Kent marine iodine at a VERY low dose, one drop per ten gallons every week, NOT the marine dose recommended on the bottle), and patience.... If the animal appears to be in distress from these growths, you might even try taking the critter out of the water and gently rubbing them off with a finger or wet paper towel if you are quite certain that they are not "normal" parts of him. Use extreme caution not to harm him if you try this.> Thanks for your help, -Brad Bennett <Best of luck to you with him, and please do try to get some pictures of this if you can; this may help in trying to find out what is wrong and how to fix it. Wishing you well, -Sabrina>
Crayfish Concerns, Medication - II - 01/24/2007
Thank you so much for the quick reply, very impressed with your comments and if I'm able I will get pictures. <That would be excellent. I'd love to continue to help you discover what this issue is, and how to solve it if it is in fact a problem.> Sincerely, -Brad <All the best to you, -Sabrina>

Crayfish Safe Ich Medication Hello crew (probably Sabrina), <Sorry, Ya got Don tonight. Sabrina's birthday today. Hope she has a happy one> I apologize for resorting to e-mailing you, but I've searched quite a bit and I can't seem to find what I'm looking for. Neptune, my electric blue crayfish (Procambarus alleni), lives in a 55 gallon tank with a small selection of plants, 2 gold Gouramis, 2 blue Gouramis, a large Plecostomus (Jacques), a dinosaur eel (Scuttlebutt), a baby whale fish, and a temporarily small Arowana. I made the hasty mistake of dumping in some small feeder guppies for the Arowana without quarantining them. Now I have a fun little (deserved) ich outbreak. I've slowly elevated the temperature to the mid-80's (Fahrenheit) and added some salt. The ich doesn't seem to be giving in that easily though, so I am going to medicate my tank. I currently have Quick cure. I understand that copper is quite unhealthy for my crayfish. The Quick cure label only lists the active ingredients (formalin and malachite green). Is Quick cure safe to use with my crayfish? If not, is there another effective medication that is crayfish-safe? Would it be best to just remove my crayfish into my empty QT and medicate the main tank? If it is, I read that the too-small-to-see ich cysts can stick to a crayfish, so would my tank be re-infested when I moved the crayfish back? Again, I apologize for bothering you, but at least now anyone else with these questions will be able to find them! Thanks in advance for your help (again). -AJ in Florida <Don't use the copper in any tank where you may someday keep inverts. Months, and dozens of water changes, later it can still kill. If your QT is large enough to house all your fish for four to six weeks, move all the fish (but not the crayfish) and treat them in QT. Leaving the 55 fishless while treating in QT will starve out the parasites. If not then you will have to move the crayfish into the QT and treat the main. Treating in the main is a last resort as the meds will nuke your bio filtration resulting in ammonia spikes. This will require that you do many large water changes to keep your fish alive, replacing the med with each. Much easier (and cheaper) in a small QT. I would use heat and salt only, no matter where you treat. Your eel and Plec will be badly stressed by copper. Possibly to the point of killing them. Salt is much easier on the fish and 100% effective if used at the proper dosage, 76 grams per 10 gallons. For a 55 gallon that works out to 418 grams or just under 15 ounces. Make a brine out of tank water and add it back over a day or two. Take the temp up to 84. When ever you do a water change add the same concentration of salt to the new water before adding it to the tank. Of course you will need to test for ammonia and nitrite during any treatment. Continue treatment for at least two weeks after the last spot drops. Always use a gravel vac to remove water. The Ich reproduces at the bottom of your tank. You have a lot of work ahead of you. Get your fish off of feeders. And oh yeah, the crayfish. Just keep him away from any fish for the four to six weeks and any hitch hikers will starve out. He can not be infected. Good luck. Don>

Crayfish/Yabby Deaths - 08/17/2005 We purchased a Yabby last week and put it in our small(ish) tank. We had been keeping danios so we were used to changing water and keeping clean etc. The water had been treated and left for 42 hours to get rid of chemicals - all seemed well. The Yabby looked well for 3 days then it became very quiet, I partially changed water, it didn't recover and died. <Any chance you have EVER used a copper-based medication in this tank? Any metal objects in the tank?> We bought another Yabby (we had liked "Godzilla" for the short time we new him). This time, just to be sure, we used our bigger tank, conditioned the water, washed the gravel and installed a filter. A day later (today) the Yabby shows the definite signs of soon demise -it's falling on it's back or side and doesn't move (except a little when I think it's dead and I go to remove it). WHAT are we doing wrong! <Not sure. I trust you are maintaining ammonia, nitrite at zero, nitrate less than 20ppm? pH somewhere between 6.8 and 8.5?> And why does it happen so quickly. My kids are scared off from getting anymore yabbies but they were so delighted with them and they paid for them themselves. Iodine is mentioned quite a bit on your site but usually in conjunction with molting problems. Neither of the yabbies showed signs of molting. <Mm, all the same, I think a lack of iodine may indeed be a problem, here.... If you do try another Yabby, please do considering adding iodine for a week or so prior to purchase.... You've seen the FAQs, so I assume you know I use and recommend Kent marine iodine at a rate of one drop per ten gallons each week (NOT the marine dose)? I have, occasionally, doubled this when adding new shrimp from somewhat disreputable stores.... My only other thought is that there may be something in the tank(s) that is actually toxic to the crays.... Copper is the very first thing to come to mind. Medications like CopperSafe, Cupramine, Aquari-sol, all contain copper. Something to think about.> Please help, Kelly (mother and grief councilor!) <Wishing your sad patients a swift recovery, -Sabrina>

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