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FAQs on Featherfin/Notopterid Knifefishes: Disease

Related Articles: Featherfin Knives, Bony Tongue Fishes, Arowanas, Arapaima, African Butterflyfish, Featherback Knifes, Mormyrids, ElephantfishesNew World Knifefishes, Black Ghost Knife,

Related FAQs: Feather Fin Knives 1, Feather Fin Knives 2, & FAQs on: Feather Fin Knife Identification, Feather Fin Knife Behavior, Feather Fin Knife Compatibility, Feather Fin Knife Selection, Feather Fin Knife Systems, Feather Fin Knife Feeding, Feather Fin Knife Reproduction, & by Species: African Featherfin Knife, Xenomystus nigri, Clown Knife, Chitala ornata, & Bony Tongue Fishes, Aba Aba Knifefish, South American Knifefishes, African Butterflyfish, Arapaimas, Arowanas, Mormyrids,

Royal knifefish sick   12/28/11
Hey guys great site first of all, its very helpful to many people. Here is my problem. I have a 18" royal knifefish that came down with a minor case of Ich. A friend of mine at the lfs recommended a product called Metroplex,
<? never heard of it, nor Google. What are the active ingredients? MSDS?>

as its all natural and shouldn't upset the knifefish.
<... I would go w/ the time tested heat (and maybe salt) treatment here.
Read: http://www.wetwebmedia.com/FWSubWebIndex/fwichremedyyes.htm
 He still recommended I use it at half does as he's a scaless fish for the first treatment.
Everything cleared up fine after dosing and raising tank temp to about 83 degrees.
<I'd raise to 86F>
Then a few days later he started showing two larger spots on his dorsal fin that were a slight brownish colour.
<Poisoned... by the med.?>
Then came the loss of appetite, he would mouth the food then spit it out. Again I raised the temp, over a period of two days and added some salt. He's back to eating again but now every night he's flashing and scraping on objects more than ever and going to the waters surface a little more frequently, breathing heavier than normal and the odd time looks like he's choking or coughing (if fish can cough). so I tried treating for skin and gill flukes with PraziPro
<... why?>
as that's the only thing I can think of. No visible signs of infection anywhere on his body aside from the two larger than Ich spots that are slightly brownish looking along with heavy breathing, coughing and flashing. Please any help would be greatly appreciated as me and my girlfriend have had our fishy friend over two years and don't plan or want to see him go. Tank parameters are 100 gal tank.
<Needs more room than this>
Perfect water quality and no other fish. Always do two small water changes a week. We like the tank clean as friends are over often. Thank you for taking time out of your day to read this. Happy holidays. PS. Pics will be available when I figure out how to post them on the site. Im not a computer guy, hence the aquariums.
<Can be sent as simple attachments. I'd do a substantial water change, change out whatever chemical filtrants you employ (carbon?) for new. Bob Fenner>
Re: Royal knifefish sick  12/28/11

After a few discussions with the lfs (big als) they seemed to think it was skin/gill flukes from descriptions I gave them on the Knifefishes behaviour.
<... where would these Trematodes come from? Do you feed live freshwater fishes to this Notopterid?
 He said also treatment may take slightly longer as I'm using the PraziPro at half strength.
<... there is no sense doing this. Id est, treating half strength. Would you treat yourself thus?>

 Tank temp has since been raised to 85-86 degrees as you suggested, also preformed about a 30% water change again yesterday
and added the proper dose of medication for water changed. Also added a slight dose of salt (sitting around. 004). As for the active ingredients in the medication called Metroplex I don't have an empty bottle kicking around, but its a product from Seachem and can be ordered off bigalsonline.ca.
could you recommend any additional treatment methods or possible diseases or infections I could be dealing with?
<... None. I would NOT be treating this fish, the system period. BobF>
Re: Royal knifefish sick  12/28/11

Found Metroplex on big als website, not, much info on it unless actual bottle is in your hand, buy here's what I got.
Metroplex (also known as Metronidazole)
<... this is NOT natural, or safe... as you'd stated in your first email>

 is an effective and safe treatment for several protozoan and anaerobic bacterial diseases of fish (Cryptocaryon, Hexamita, Ichthyophthirius). It does not adversely affect the filter bed and is easily removed with carbon. There is little danger of overdosing. For freshwater and saltwater applications.
<See my writings posted on WWM. Toxic>
Manufactured by: Seachem Merchant SKU: 20173 Safe and easy treatment Heals parasitic and bacterial infections Will not affect filter bed Easily removed with carbon
Im no longer using this medication.
re: Royal knifefish sick  12/29/11

So do you suggest I put in carbon to remove the medication for a while and see how he reacts?
I did this when I switched from the Metroplex to PraziPro. I gave it two weeks without medications then that's when these problems started thus the treatments with PraziPro. Im stuck not knowing the proper next step to take without advice from someone other than the lfs. They are helpful, but not in the same ball park as you guys a wwm.
<We are many more folks w/ likely considerably more academic and practical experience. There are many good folk in the retail side, and some that aren't quite there yet. BobF>
Re: Royal knifefish sick    12/30/11

Thank you very much for your help. I will try what you suggested and we shall see what the conclusions are in a week or two's time. Again thank you for your advice.
<Welcome Kyle. BobF>
Re: Royal knifefish sick
Hello again Bob, hope new years treated you well.
<And you Kyle>
It looks like the knifefish may have gotten slightly worse since I stopped all treatments a few days ago. I have performed several water changes and had water tested by a close friend of mine with a test kit and everything showed up literally perfect but a little on the soft side (new water softener installed at home a few months ago). The Knifefishes appearance has not changed, no visible sign of infections at all aside from those small Ich spots that still show on his dorsal and pectoral fines (maybe two visible spots on each fin).
But now my main concern is his behaviour, it still looks like he's choking the odd time or just breathing heavier than normal,
<These are actually quite normal behaviors of Notopterids. Have seen myself many times>
he's mostly lazy during the day which is normal for him, though literally when the lights go out he starts flashing and scraping on objects in the tank.
<This too>
But he's mostly scraping his face area. He will go to the filter arm and rub his face on it then dart away or swim right into the thing making a loud noise. This activity has been increasing daily and same with grabbing air at the water surface.
<And this>
 Still when I mention this to the people at the lfs they say Ich or gill flukes.
<... No>
Do have any idea what I could be dealing with and how to treat this?
<Yes. I would do nothing here, other than regular maintenance. This fish is just recovering from the ill-effects of your treatments>
its been a problem for about two months now and I'm tired spending money and stressing out over it. Im starting to lean towards getting rid of the damn thing and letting the tank run empty for five weeks then start over with a new fish. I need a solution here.
<Simply time going by. BobF>
Re: Royal knifefish sick    1/4/12

Ok... I have seen many knifefish in their nocturnal state and mine is the only one doing this behaviour. The first two years I had him, his nightly behaviour was very calm, he would slowly roam and patrol the tank, its ever since the Ich problem he's acted totally different at night by scratching his face on everything.
<From, hopefully for the last time, your "medicating">
So do you think this odd behaviour will stop in time and he'll go back to his normal behaviour?
 Its hard to watch him do the odd things he does and not think there's something wrong.
<Was poisoned....>
 His tank conditions are back to normal, temp at 75 and pristine water quality. Im starting to think I'm maybe too paranoid or worried about it.
<Take a chill pill and learn the value of patience. B>

Re: Royal knifefish sick   1/8/12
Hi Bob. Seems the knifefish has showed some signs of improvement, mainly with his breathing and breaking the water surface.
<Ah good>
I have included some attachments for you to have a look at. Im not sure weather these marks on his body are just skin damage from his nightly spazzes or if its some sort of fungal infection.
<The former>
Other than adding some salt to help heal the skin wounds, is there anything else you can recommend I do to help him out?
<As I've repeatedly said, just good care... I would NOT treat>
He has a couple different marks on him but these were the best I could do with a fish who wont sit still.

Black clown knife with pop eyes?   2/25/09 Hi! Hopefully you can help me with a problem..within the last week. my black clown knife's eyes have been bulging and they are getting worse. I have done a 50% water change. but the BCK is now swimming by the top and I want to help him. but don't know what meds to give him. Can you help? Thanks! Karen <Hello Karen. With Popeye, there are usually two causes. If there's just one eye popped, it's likely physical damage or aggression, so you need to look at things from that angle, checking the tank is big enough for the fish, doesn't contain aggressive tankmates, and so on. If both eyes show a similar degree of swelling, it's usually an environmental issue, in which case you need to review water quality and water chemistry stability. Clowns are big, messy fish and need extremely generous filtration to stay in good health. For an adult specimen (at least 60 cm/24 inches in length) you'd be looking at a tank around 750+ litres (200+ gallons) in size and equipped with a filter rated at 8-10 times the volume of the tank in turnover per hour. 50% weekly water changes would surely be essential. I'm mentioning all this because unless the environment is fixed, the eyes won't heal. So far as treatment goes, an antibiotic like Maracyn coupled with Epsom salt in the water at 1-3 teaspoons per gallon should do the trick. http://www.wetwebmedia.com/popeyefaqs.htm Cheers, Neale.> Thank you for your help! :0) I do appreciate it! :0) -Karen <Happy to help. Good luck, Neale.>

Clown knife problem 7/5/05 Dear Bob,            I hate to  bother you with this, however you seem like one of the only people that might be  able to help me.  I have a clown knife, approximately 7 inches long.   He was accidentally overfed and became grotesquely bloated.  I haven't fed  him now in a month, yet the bloating has not gone down.  I spoke to the  owner of a local fish store who advised me to add salt to the water.  I  have been doing this but it doesn't seem to help.  I have never seen this  before and I am having a difficult time finding anyone who can help.   <Mmmm, what sort of salt? I would try a level teaspoon of Epsom (Magnesium sulfate) per ten gallons of water>     Have you ever seen or heard of this before?   If so, what should I do?   If not, can you refer me to someone?  Thanks  again for your time. Warmest Regards, Janet Sanders <Some sort of gut blockage... what were you feeding? Hopefully not goldfish... Bob Fenner>

Re: clown knife problem 7/6/05 Dear Bob, <Janet>             Thanks  for the quick reply.  Unfortunately, it is goldfish.  I had fed my  fish the night before leaving on a business trip.  The next day, my son  (not knowing I had just fed the fish), fed them again -- my fish has been sick  since.  What should I do? Thanks, Janet <Try adding a level teaspoon of Epsom salt per ten gallons of system water... Hopefully this will "move" the blockage. Bob Fenner>

Clown Knife With Problems  12/24/05 Hello, I've skimmed over the articles on clown knife fish and haven't really seen anything about what I've got to ask .Recently I purchased two clown knives. Each is now no more than six inches long. For now, each is in a separate tank until I can get one larger tank at the beginning of the year. Both are fed live feeders , which I'm beginning to learn isn't the best idea , but one will take shrimp pellets at times . I have been unable to find squid  ( other than at the grocery store and am not sure if that's the correct way to feed them) or live krill in my area.   One seems to be getting a little fatty in the belly. At first I simply took this to be a by product of  healthy feeding because this fish can put away the little live feeders . Only now the seemingly distended belly remains . I don't recall it's sides poking out so when I first got it. But at the pet store both of the fish were in the same tank with several other kinds and now it has much more elbow room.   I also keep my tanks and filters clean on a bi-weekly basis. I haven't had any outbreaks of any kind among any of my fish for a long time.   My question is : Is my fish healthy? <A fish that has a distended belly doesn't sound too good.> Overfed? < Clown knife fish can be real pigs. It is easy to over feed them.> Or ,possibly , infected by some internal parasite and ,if so, how can I be sure and what treatments would be necessary? < It could be an internal bacterial infection. If it is it needs to be treated with Metronidazole .> And if the fish is healthy - does that mean the slimmer one isn't and I should up it's rations? < I would feed no more than can be consumed in two minutes once each day.> Something which may be related : How often should Clown Knives be feed ? Daily ?Or just every other day ? < Bigger knifes can be fed a couple times a week as their metabolism slows down as they grow.> On a side note , Do you receive many complaints about pet shop owners either giving less than knowledgeable advice or just not giving any to people ,especially those just getting into the raising fish , purchasing the more exotic fishes - outside of the guppies , goldfish , mollies Etc.? < If pet shops and fish store were giving good advice all the time then we would not be answering questions.>        It's just that I've had to make major tank purchases and accommodate them within my home simply because the seller did not elaborate on just how big some of these fish can get. I know they are in business to stay in business through sells and I have gotten better informed since I began but in listening to other customers when making their choices I rarely hear the seller say ' How big of a tank do you have ? or What other kinds of fish do you have in it ?'       I've come to deal with only one seller in my small area and I've learned and am still learning the  right questions to ask but even then I don't get the entire story .       What worries me is that most people I meet can tell you ' Yes , an Oscar can get very big ,' but they couldn't tell you  how large a clown knife can get or an electric catfish  and yet when they step into the pet store and see that fish and think to themselves how neat it would be in their tank , the seller does little to inform or dissuade . I've grown to enjoy and love fish in the last year  but  if  I'd never messed up and purchased an electric catfish when I was just starting out  I'd never would have learned what I have. However there must be so many fish that get flushed or die from lack of proper care  simply because the buyer wasn't informed and was ignorant of the fact he/she needed to be . It may be different in a large city or other areas but I think there should be some movement towards having the tanks at the pet stores labeled as to level of care , mature size/ min. tank size , proper food and  feeding because often the owner maybe absent and the clerk may just not know and the customer as well as the fish deserve better. Thank you for your time, Thomas Tuck <It is a business, like any other, to make money. Unfortunately ignorance at all levels of this hobby is something that we here at WWM try to overcome everyday. Find a store that gives you good service with a friendly knowledgeable staff and continue to patronize that store even if their prices are not the lowest. Nobody knows everything. That's why we have a crew here instead of just one person. Next time you see a fish that looks interesting I would recommend that you go over to the book section of the store and try to find out some info about it before purchasing the fish.-Chuck.>

Need Help I am at a complete loss, and I'm now turning to online resources in my desperate attempt to find a solution to my problem. I found your site to be very impressive; very rarely does one find a resource that contains such a wealth of valid information. I work at a large chain pet store, in the aquatics department. All of us in the department are extremely knowledgeable about fish and their care, and rarely have any problems with any of our fish. However, whenever we receive a shipment of black ghost knives or clown knives, the fish systematically die off within a couple of days. We have no problem with our brown knives, ever. We keep each species in their own tank, the brown knives in a larger tank with zebra Danios (they never come in large enough to eat the Danios), and the ghost and clown knives in their own smaller isolated tanks. We offer ample hiding spots for each type of fish. We feed each frozen food, such as bloodworms, nightly. Our pH is a little high, around 7.8, and our water hardness is through the roof, but our temperature is a consistent 78 F. We always carry juvenile fish; the knives never come in larger than 4 inches or so. We would like to carry ghost and clown knives, but not if it means continuous losses such as we have experienced. If you have any advice as to what we might be doing wrong, and what we might to do rectify this, it would be greatly appreciated. My thanks in advance. L Barker  <<Hello. I need to know if you guys are putting these fish into properly cycled tanks. I know it sounds simplistic, but it would make me feel better if you could provide me with information on ammonia levels, nitrite and nitrate levels in these tanks. The problem with being a store is that as the fish are gradually being sold, over time, the beneficial bacteria can die off without us being aware of it...then along comes a new shipment, and twenty fish are suddenly put back into tanks with limited bacteria. The ammonia level can skyrocket the first few days, resulting in sick knife fish that never fully recuperate due to all the stress from shipping combined with new surroundings...and undoubtedly bad nutrition before you received them. Also, smaller knives are even more sensitive than larger ones. You may have a better survival rate if you can specify 3 inches or LARGER when you order your knife fish. Try, and see. In the meantime, prepare your knife fish tanks either by keeping them full of other species at all times to keep the biofilter alive, or by using pure ammonia to keep the nitrifying bacteria alive, until the shipment lands. You can also try running some peat moss to help lower pH and hardness levels, though these, in and of themselves, should not be enough to kill all the newcomers alone, but it doesn't help when added to the other stressors the fish are facing. Also, keep in mind that knife fish are aggressive amongst each other, and make sure to provide plenty of PVC tubes for the ghosts, at least one per fish!! Keep the lighting low for the first few days, as well. You can cover the tanks with Styrofoam lids to diffuse the lighting, or leave the lights off entirely. -Gwen>>

Clown knife with a bulge My clown knife looks as though it has swallowed a small rubber ball.. the kind that you get out of a gumball machine...   All of my other fish are still in the tank and still have all of there parts... my clown knife will not eat now but is moving around fine... <Is the clown producing feces at all?  If so, is it normal and brownish, or white and stringy?> We have had Mercury for 2 months now and have NEVER seen this before... I understand and have seen the "bulge" after eating, but this is NOT that!! The bulge he has now is huge and very round, again, like he swallowed a rubber ball.. no other way to describe it... <Sounds very much to be a gut blockage or constipation.  I'd suggest to dose the tank with Epsom salts at a rate of 1 to 2 tablespoons per ten gallons (this *should* help), and if the fish looks like he may accept food tomorrow, offer daphnia or mosquito larvae, or possibly (depending on size of the fish) a small earthworm, if the other items are too small for him.  These foods are high in roughage content and may possibly help to pass the blockage.> The owner of the local pet store thought maybe it was a bladder infection <Hmm....  a swim bladder infection is characterized by abnormal swimming (and occasionally accompanied with dropsy) - I do not believe this to be the case.> and told me to wait until tomorrow and see how he was.... <Go ahead and dose with Epsom salts tonight, it may very well help a great deal.> I cannot find ANYTHING on the net regarding this.... CAN YOU PLEASE HELP????? <I do wish to bring up another issue that this may be - there's the possibility that this is a tumor.  That you seem to imply that it happened suddenly and that the fish is not eating lead me to think constipation far more likely.  If it is a tumor, though, there's really nothing to be done, unfortunately.  Hopefully you'll see some improvement soon.> Thank you in advance....  Heather O <Wishing your fish a quick recovery,  -Sabrina>

Clown knife with a bulge - II THANK YOU very much for the speedy reply!!!!!   <You bet!> This morning when we checked in on him.. the one side has gone down completely and the other side is much smaller but now , no other way to explain it.... but it looks like a huge zit with a white head... half an inch long by 1/8 of an inch wide... <Hmm.  That doesn't sound good.  possibly an injury, perhaps infection....> it definitely looks better than last night at 9:00pm.... <That's certainly a good sign!!> as for producing feces.. I am not sure... <Sounds like he passed the most of it.  Still, do try to feed foods with a high roughage content for a few days.> Mercury is about 7 inches long now... and has been doing wonderful until last night... he gets along great with our other clown knife Neptune, who is about 12 inches.... we also have a convict, a scat, an iridescent shark, and a Plecostomus...all live happily together.... <You seem to have a taste for the very, very large....  Ultimately, hope you've got a really big tank!  ;)  > He still isn't eating... but as I said.... I think that he looks much better.... <Good.> Again, thank you SOOOO VERY MUCH for the speedy reply... this is a site that I will keep handy in the future!!! <Excellent.  Pass it along to all your fish friends, too!> Oh, I almost forgot... I do have aquarium salt in the tank... but will add Epsom salt if you still think that will help! <I do think it would help, perhaps, especially if Mercury is still a little bloated.  Also, please keep a *close* watch on that strange mark - if it's an infection of some sort, you'll want to quarantine and treat with an antibiotic.  Hope all goes well, and glad to be of service!  -Sabrina> Heather O

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