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FAQs on  Corydoras Cat Disease Treatments

FAQs on: Corydoras Catfish Health 1, Cory Disease 2, Cory Disease 3, Cory Disease 4
FAQs on Corydoras Catfish Disease by Category
: Environmental, Nutritional (e.g. HLLE), Social, Infectious (Virus, Bacterial, Fungal), Parasitic (Ich, Velvet...), Genetic,

Related Articles: Callichthyid CatfishesSummer loving: cats in the garden, kittens in the kitchen by Neale Monks,

FAQs on: Corydoras Catfish 1,
Corydoras Catfish Identification, Corydoras Catfish Behavior, Corydoras Catfish Compatibility, Corydoras Catfish Stocking/Selection, Corydoras Catfish Systems, Corydoras Catfish Feeding, Corydoras Catfish Reproduction,
FAQs on: Panda Corydoras, Pygmy Corydoras spp.,

FAQs on:
Callichthyids 1, Callichthyids 2,
FAQs on: Callichthyid Identification, Callichthyid Behavior, Callichthyid Compatibility, Callichthyid Selection, Callichthyid Systems, Callichthyid Feeding, Callichthyid Disease, Callichthyid Reproduction, Catfish: Identification, Behavior, Compatibility, Selection, Systems, Feeding, Disease, Reproduction

As usual: KNOW what you're treating (for). Not salts in general w/ this genus. NOT anti-fungals w/o fixing the root problems with environment. NOT harsh dyes, metal solutions, or formalin. NOT phony med.s like Mela-, Pima... non fixes

 

Costia on Bandit Cory(s), invert safe treatments?          5/27/15
Hi, I have a planted 65 gal tank 4 years+ running with honey gouramis, kuhli loaches, Hengle's Rasboras, bandit Cory's, Amano shrimp, Nerite snails, Oto cats. I think the Oto cats brought in disease and I had some loses of livestock and then things seemed to stabilize with no more dying fish. Some of the Cory cats, one in particular, have gray slime on them that seems to be 'Costia'.
<Costia, now called Ichthyobodo, is an awkward parasite for sure. It's one of the causes of Slime Disease, though not the only one, so do be aware of that. Curiously, but significantly, Costia is harmlessly present in most tanks, and only becomes problematic when the fish become stressed. So it's important to try and think of why that might be the case. In any case, there are various proprietary treatments out there, such as eSHa 2000 (no formalin or copper), QuickCure (has formalin in it though) and Interpet Anti Slime and Velvet (this latter also contains formalin). Otherwise, apart from formalin (which does indeed work well against Costia) any metrifonate-based medication should work well.>
I have gradually turned the heat up from 77 F to 83 F. The slime seems less on the worst Cory but still there. I can't net them out of the tank, too many obstacles. The invertebrates make using most of the medications recommended for Costia not safe to use.
<Indeed. Anything with copper or formalin in it may be toxic to shrimps, snails, and potentially sensitive fish including loaches and catfish. So you've got problems.>
Is there anything else that I can/should be doing? Does Paraguard have any effect on Costia?
<Paraguard has a chemical similar to formaldehyde in it, so wouldn't be an obvious choice for use with your community of species.>
Prazi-pro did not help at all.
<Obviously not. It's a dewormer.>
Thanks,
Jeff
<Cheers, Neale.>
Re: Costia on Bandit Cory(s), invert safe treatments?      5/28/15

I'm not sure if I can get eSHa 2000 here in Canada. I'll look around.
<Or order online, via eBay, etc.>
The inverts in this tank have been through Paraguard treatment before without losses. I've never had it obviously cure anything, but if you think it would have a chance at Costia I'm willing to try it. I have a bottle handy. Should I adjust the dose for the Cory cats or Otto's?
<Adjusting doses down is fairly pointless. Generally the dose stated on the bottle is the dose needed to kill the parasite. Half doses might work, but then again, they might not. You could consult with the manufacturer for
guidance. SeaChem do have an FAQ, here:
http://www.seachem.com/support/FAQs/ParaGuard.html
They don't sell this product as "reef safe" as you can see, which means it might be toxic to invertebrates... but then again, it might not! That's probably about as sure a reply as you're going to get on this product.
Cheers, Neale.>
Re: Costia on Bandit Cory(s), invert safe treatments?      5/29/15

I tried the Prazi-pro first because I thought it might be skin flukes. I'll try the Paraguard after I do a water change on the weekend and see if that helps. If I go much higher with the water temps I am going to lose some plants.
I'll let you know if it seems to do anything.
Thanks, Jeff
<You're welcome, Neale.>
Re: Costia on Bandit Cory(s), invert safe treatments?        8/15/15

Hi Neale,
<Jeffrey,>
Is been awhile but I thought that I would let you know that the ParaGuard did not do anything. However, I had some PolyGuard and that cleared up the problem with 2 doses, maybe 3, I can't remember exactly.
<Cool.>
I have another question. I switched my tank to Fluorite black sand substrate about 5-6 months ago because I thought the eco-complete was too sharp on Cory cat and other bottom feeders barbels.
<Ah... not the best idea.>
Frustratingly, Cory cats I have put in there since have still developed eroded barbels.
<Yes. Fluorite sand is, as I understand it, manufactured, not a natural product. It isn't a natural substrate and remains sharp enough to cause problems for bottom dwelling fish. An excellent choice for Amano-style tanks with midwater fish (tetras for example) but not for catfish, loaches and so on.>
I know bacteria is another possible cause of this but the question is how to avoid it.
<The erosion of the catfish barbels is a two-step process. The sand creates scratches in the skin tissue, and bacteria (similar to Finrot) can get in. Whether there's a threshold of dirtiness required for this second step I do not know, but I'd assume not because catfish whiskers are just fine in silica sand tanks with lots of organic detritus, which would seem to have more bacteria than clean fluorite sand.>
I do a 30 percent water change every week and the tank is not heavily stocked. It is a planted tank, so I do not vacuum the bottom during water changes.
<Generally no need.>
There are two AquaClear filters and a circulation pump, so there are no noticeable dead spots with piles of waste building up in them.
Thanks,
Jeff
<It's the sand, Jeff. Swap it out for plain vanilla smooth silica sand from a garden centre or pool filter sand supplier. Will look hideously bright at first, but over time the grains darken (algae and bacteria, I guess) and you'll find it much more agreeable. Alternatively, replace the Corydoras with a midwater catfish species such as Dianema spp., Asian Glass Cats,
African Glass Cats, or even Dwarf Upside Down Cats. Cheers, Neale.>

Corydoras dying  - 10/22/2012
Hello. I've been having this fairly recent problem with what started as a school of 8 mixed Corydoras (two skunks, two julli, two elegans, two false bandit).
Around July I lost a skunk Cory, a week later the other skunk died. I wasn't sure if that was just a fluke.
Then about a month later it was a julli, and now just a week ago I noticed one of the false bandits surfacing a lot, and resting in my floating plants, emaciated and not looking very good.
<Mmmm>
I noticed his fins were torn,
<What other livestock here?>

 so I set up a large clean container, put an airstone in, and put him and the other false bandit (also torn fins, no barbels) in there, treating with MelaFix and PimaFix combined,
<Worthless; search WWM re>

 at least for the sake of the second one. The very sick one was laying on his side at first, and the next day I checked and he was sitting upright.
On the third day he died, but I continued treatment for a week for the second one, hoping to help with torn fins. After I saw some regrowth I eased him back into the 55. I noticed he was breathing rather rapidly, but I figured it was just from the whole acclimating deal. Yesterday he was active, until he swam up and rested in the same spot of plants the other one did. Today I found him dead by the filter. That was the only one who didn't show the usual symptoms, besides not really eating.
Symptoms include lethargy (even for a Cory), no interest in food, and eventually they get skinny and die. Not all of them have had torn fins. The tank was started last December and is a 55 gallon stocked with the 3 remaining Corydoras (2 elegans, 1 julli) 8 neon Rainbowfish, 10 harlequin Rasboras, 6 Madagascar Rainbowfish, 5 zebra danios, 1 Bristlenose plecostomus,
<This Ancistrus may be the root of trouble here>

3 banded mountain loaches, 5 Kuhli loaches, 1 survivor Oto, 1 dwarf gourami, 5 gardneri killifish, 3 flower shrimp and 1 Rhinogobius wui/duospilus that I'm trying to move to his own 10 gallon. Ammonia and nitrites are at 0ppm, nitrates under 20ppm.. The pH sometimes fluctuates a little during water changes because we have very hard city water, and the driftwood in the tank ends up buffering that to around 7. Temperature is at a consistent 75 degrees Fahrenheit. The tank is planted, with dirt capped by gravel. (I know gravel's a no-no for them, but I wasn't aware at the time of buying them of how detrimental it could become) I do weekly 15-20% water changes.
At first I suspected the banded mountain loaches were hogging the food, because they're quite voracious eaters, squabbling with each other and guarding their food, but I'm making sure the cories are getting some I feed algae wafers, shrimp pellets, frozen bloodworms, frozen brine shrimp, and frozen glassworms. When I have the worms out, the elegant cories will eat from my fingers, so I feel better about that. Not sure of the best way to treat my remaining 3, because I'm fairly positive it's only a matter of time. I'm thinking parasites at this point, but what would you suggest using or trying?
<Removing the Loricariid or the Callichthyids to elsewhere... separating them. Someone, something is beating on them...>
 But then if it were parasites, wouldn't my other fish be showing symptoms?
<Likely so; yes>
 Everybody else has been seemingly healthy. Even the cories, though they aren't terribly active, have little full bellies until their last week.
Advice is greatly appreciated.
Thanks,
Sarah
<I have experienced such troubles myself twixt these catfishes... Some "Plecos" will "ride" other fishes... cause them health issues by sucking off their body slime... Bob Fenner>
Re: Corydoras dying     10/23/12

I don't really think it's the plecostomus,  because he tends to stay on his driftwood,
<Not during the night; this is when they're most active>
 but I don't think it'd hurt to move them and see what happens.
<Good>
Wouldn't there be some kind of visible evidence on the fish if that was the case?
<Mmm, yes... the torn fins you mention, a lack of body slime and what it portends... infection, death>
 I wondered if Corydoras have some sort of specialized disease, like dwarf gouramis can get "dwarf gourami disease", or how neon tetras can get "neon tetra disease". But I haven't heard of it. Just a thought.
<Corydoras do die more easily given some types of stress, conditions, but no specific pathogens as far as I'm aware>
Do you think I should move the three into my recently cycled (started on Oct 2. It cycled quickly.), heavily planted ten gallon and see how that goes?
<Yes... with a good deal of the current water, perhaps a bit of "mulm" siphoned from the older tank's gravel>
 Right now it just has one Danio. She's my 'ammonia source' for now.
There IS small gravel, for substrate, but oh, well. Wasn't planning on more cories, because I've just had the *best* luck with them.
If it so happens that there's an internal parasite involved, what would you treat them with if it comes to that?
<... would depend on its diagnosis, identification. I myself would not simply "blast treat" w/ anti-Protozoals, Anthelminthics et al. w/o knowing what I was treating. BobF>
Thanks,
Sarah
Re: Corys dying      9/3/14

Hi Neale,
<Joanne,>
I want to thank you for your advice.
<Most welcome.>
I treated them with antibiotics and the flashing and deaths stopped.
<Good.>
I started after a month of no issues when it started to happen again.
<Strange. Anything added to the tank (new livestock for example) or dramatically changed in their environment?
I treated with antibiotics again and they seemed to work for a few weeks, but my remaining cories have started dying at a rate of one every 10 to 15 days. It's strange as they are eating fine and show no sign of illness until the flicking starts. It is also happening one by one, rather than affecting them all at once.
<Yes, have seen this pattern.>
At this stage I am thinking all I can do is wait and see. I only have 5 left and I am hoping if it is a parasite that once I have lost them all which seems inevitable, maybe it will die out with no hosts and I may be
able to start again with my cories by the end of the year.
<Possibly the case. Agree that leaving the tank without Corydoras for a few weeks or months would be beneficial. But likewise, removing the healthy specimens to a quarantine tank could achieve the same thing. A clean QT tank, ideally with no substrate, would provide optimal conditions, and you could more easily detect problems and react accordingly. For Corydoras, even a 10-gallon tank can work for QT purposes just fine. Air-powered sponge filter adequate, and you might possibly not even need a heater
(Peppered and Bronze Corydoras fine at 18 C/64 F, and the others fine down to 22 C/72 F; nighttime dips below these temperatures won't cause problems if just a few degrees).>
No other fish have been impacted during this.
<Curious. Does seem to be either a specific Corydoras pathogen or else something problematic in/about the substrate (always a suspect if it's benthic fish that are sickening but not midwater species).>
Anyway, I do appreciate your advice and I wish I could give you a happier update.
Kind regards,
Joanne
<Hope this helps, Neale.>
Re: Corys dying   9/5/14

Hi Neale,
<Joanne,>
Thanks for getting back to me so quickly.
<Welcome.>
I added an Anubias plus a sword plant and two flying foxes (Crossoheilus) to prevent algae. I have not made any changes to my maintenance routine.
<Anubias will do nothing to prevent algae. On the contrary, they're algae magnets because their leaves grow extremely slowly (they don't attract algae as such, but they don't have much way to inhibit algae growing on them, unlike many fast-growing plants). Really, floating plants and other very speedy growing plants like Hygrophila are the "algae busters" under appropriate lighting. The Flying Foxes are fair to middling algae eaters, very territorial, and unless your tank is exceptionally big, two will probably fight a lot. They aren't an alternative to Siamese Algae Eaters.>
The only other change I want to make is to add maybe 8 - 10 rummy noses (bleheri) as I am looking for something which will bring some nice schooling behavior to my tank.
<An excellent choice though this species is touchy and does need softish water to do well; 1-12 degrees dKH, pH 6-7.5 is about right.>
I will get the cories out over the weekend and see how they go.
<Cool.>
I have noticed a few small bristleworms in the substrate when vacuuming, so I am being more careful with feeding as I understand that these appear when excess food is left in the tank. Not sure how they got into the tank though, as I always run new plants under the tap to get rid of snail eggs first.
<Indeed. Small worms in freshwater aquaria rarely cause problems. Nothing like the bristleworms that plague marine tanks. Mostly the freshwater worms are planarians (neither good nor bad) or oligochaetes (quite beneficial).
Nematodes may be seen too. Freshwater polychaetes, i.e., truly bristly worms, are exceedingly rare. Do review these groups to aid your
identification.>
Kind regards,
Joanne
<Cheers, Neale.>

Re: Sudden sickness? Panicking... Corydoras... Hypochondria     11/24/12
Hi Bob.  Well I'm still having troubles.  Since I thought the medication (was treating with Maracyn and Maracyn 2) was causing the Corys to have a bad reaction (Albinos swimming frantically, Peppered listless), I decided to stop the medicines for a day, do a 50% water change, and insert a carbon filter.  The next day the Albino Corys were still swimming frantically, but the Peppered Corys showed improvement and were more active.  So I decided to continue treatment with just one medicine, the Maracyn (carbon filter removed).  So in total, the Corys and Honey Gourami had two days treatment of Maracyn and Maracyn 2, one day break, then three days of just Maracyn.  The directions say to treat for 5 days, which I did, but I'm not sure if the 1 day break caused a set back. 
<Not likely much>
The last day of treatment was 7 days ago.  The Corys seem improved; no more frantic swimming, basically active.  The Gourami is more active than before but she is still
spending a lot of time on the bottom of the tank, in corners.  I noticed she looks slightly swollen in her abdomen.  When she is on the bottom, she sometimes has her head down and tail up (although no longer leaning to the side, which she was doing prior to medication).  Before she had some stringy feces, but they were not white (they were green).  Her feces now look normal.  So I'm thinking the Maracyn may have helped a little bit, but hasn't cured her.  I'm leaning towards Hexamita, even though her feces aren't white.
<Which the Maracyn products won't treat>
  I considered dropsy too, but she isn't grossly swollen, and her scales are not protruding.  She is still eating, but mostly the sinking pellets; she isn't noticing the flakes at the top of the tank (unusual).  And while eating the pellets, I noticed today she kept swimming to the top of the tank to take quick breaths.  She is also still acting skittish.  But, considering the Hexamita, I don't see any thinning on the top of the head, no holes or lesions,
<Might just be lumenal, or sub-clinical>
 and she is not swimming backwards.  So, with the symptoms she does have, would you recommend treatment with Maracyn 2 or Metro?
<The last>
  As a side note, 9 months ago I had a Guppy in his own tank who became afflicted with Hexamita.  I treated him with Metro and he seemed to have recovered, but then passed away a month later. 
<Mmm, could be... most anything. But Metronidazole is quite toxic; should not be repeatedly applied>
I was careful not to cross contaminate.  I was also curious if the dead snail could have infected the fish with anything (I've heard a lot about the parasites snails carry).
<Possibly>
 On another note, the tank is still barren, except for 3 live plants (Anubias, java fern).  Thanks for your time and input, Lorie
<BobF>
 Re: Sudden sickness? Panicking...    11/24/12

Hi again.  I checked on the Gourami right after I emailed you and she seems worse.  She's sitting on the bottom still, but now she's breathing hard.  And she is leaning a bit after all.  So i did a water change (which uncharacteristically scared her), and decided against Hexamita after all and began treatment again with Maracyn 2.  I decided this because when I treated her before with Maracyn 2, she showed some improvement.  Since she doesn't have the stringy feces or loss of appetite, I concluded she has an internal bacterial infection.  Well anyways, I'll see how she does/if she makes it by morning.  Thanks, Lorie
<B>
Re: Sudden sickness? Panicking...    11/24/12

Never mind Bob. I did another water change then treated with the Metro. If the Gourami shows improvement, then I will try to feed her the Metro as well. Thank you for your patience and help. -Lorie
<Glad to share what I can. B>
Re: Sudden sickness? Panicking...    11/24/12

Thanks for your reply.  Well I already treated with Maracyn 2 last night, and this morning the Gourami is the same; sitting at the bottom, breathing hard.  She's swimming a bit too, but she'll swim up and down, almost in a straight line, with her nose to the glass wall; I don't know if that tells you anything, it just seems, neurotic maybe?  Or she's unsettled.  This is so discouraging.....since I already treated with Maracyn 2, what would you recommend at this point?  Thank you, Lorie
<Perhaps the default dual treatment (four additives) of Metronidazole and an Anthelminthic... B>
Re: Sudden sickness? Panicking...    11/25/12
Hi again and thanks. So I'm treating the water with Metro, and I attempted to feed with Metro too. I read an article that said you can bind the Metro with dry food using fish oil; it kind of worked. I believe the Gourami got some medicine in her. I'm going to try to bind medicine to the sinking pellets for the Corys. As far as the anthelminthic medicine; is salt a viable option?
<For treating for worms? No>

If I use salt, do I raise the temp of the tank?
<N/A>
 Should I vacuum the gravel since the fish ate the Metro, and since they will receive another antiparasitic medicine?
<I wouldn't increase the regular maintenance>
Or is another medicine a better option than salt? The Mardel line recommends Coopesafe
<CopperSafe>
for parasites, but is that safe for Corys?
<... is too toxic and unneeded. A timely note: MANY more captive aquatic specimens are killed by mis- and over-treating than from pathogenic disease. BobF>
Is there a specific medicine you recommend if salt isn't a good idea? I have a 10 gallon tank, 1 Honey Gourami and 5 Corys. Thank you! -Lorie
Re: Sudden sickness? Panicking...     11/25/12
Maybe I misunderstood; in your last response you recommended a dual treatment of Metro and an anthelminthic drug. That's why I was asking about salt or a recommendation for an anthelminthic drug. -Lorie
<... no; Please learn to/use the search tool, indices on WWM. Read here:
http://www.wetwebmedia.com/FWSubWebIndex/AnthelminthicsFWF.htm>

Cory cat question, hlth. mostly 7/27/09
Hello,
<Hello,>
First here the specifics of my tank:
nitrates/nitrites= 0
pH= 7.2-7.4
Temp- about 70-75 degrees F
<While this low-end range is idea for most (though not quite all) Corydoras catfish, it is a bit low for most other tropical fish, so do be careful what you add. Platies, Otocinclus and Cherry Shrimps should thrive in cool, well-oxygenated water, but Bettas, not so much.>
Light- fluorescent for 12 hours a day total (timer is set for 2 hours on then a half hour off during the day so the bulb and ac/dc converter don't over-heat)
Plants- 6 small, broad leafed plants and driftwood
Size- 12 gallons
<Bit on the small side for adult Corydoras and Platies.>
Inhabitants: 1 male Betta, 3 female platy's, 1 small otty, 3 spotted Cory cats, a couple of cherry shrimp (I just noticed some babies too), more snails then I would like (and are constantly removing!)
<Keep your tank clean. Snails convert waste, particularly uneaten food and dying plants, into baby snails. The cleaner the tank, the less the snails can breed. Adding something like Clea helena (the Assassin or Snail-eating Snail) also works wonders. They're widely sold in England, and perhaps elsewhere.>
water change: 25% every 7-10 days, I treat the water with a water conditioner before adding it and match the temperature.
Background:
All fish have been together for about 2 months and get along very well (no biting or chasing, no one has damaged fins, all are active and eat well)
Problem:
I had a 4th Cory who about a month ago (1 month after I got it) became sick. I first noticed it would stay by itself, it lost weight, and its tail fin was slightly clamped and a little red at the base. I treated the tank with an anti-fungus agent containing Nitrofurazone, Furazolidone, and potassium dichromate as per the directions.
<Why did you treat for Fungus? Were there symptoms of fungal infection?
Just to recap: Fungus looks like tufts of short white threads. It's often compared to cotton wool. If you don't see this symptom, then Fungus isn't likely, and use of anti-fungal medications is a waste. Do always remember medicines are poisons! Overuse, or careless use, will cause harm.>
There was no change in the fish and he/she became increasingly lethargic and started having labored breathing (the tail was still clamped and the redness was spreading from the base towards the tip of the fin). I retreated the tank after 4 days and a water change (as per the product's directions) and there was still no change in the fish and all the other fish showed no symptoms. Finally, after about a week the fish died. The tail had white fuzz on it, it was very red and there was some marked degeneration when I found him in the morning.
<Now, white fuzz, which can be Fungus, will often appear when a fish has died, or is close to death. Fungus is part of the natural, healthy ecosystem in your tank. Among other things, it breaks down fish faeces into the chemicals the biological filter can process. But the flip side is that a moribund or dead fish is every bit as delicious to fungi as a lump of fish faecal material. The fungi just eat whatever they can find. In your case, this Corydoras may well have been sick because of something else, and the fungus was just an opportunist that jumped onto the fish as it was dying.>
I figured this was just a weak fish but then 3-4 days ago (its been about a month since the above fish died) another Cory has the same symptoms and all my other fish look completely healthy (I haven't added any new plants or fish in the interim). I tried the same fungus killer and it hasn't made a difference. The fish is getting worse and I doubt he'll be alive by tomorrow morning but I am worried that this will keep happening to my other fish and I do not know how to treat the water.
<First of all, what is the water quality? Corydoras must have clean water, so 0 ammonia and 0 nitrite are critical. Secondly, the water must have too-extreme a set of chemistry parameters. Aim for pH of 6 to 8, 5-20 degrees dH. It doesn't matter precisely what the values are, just that they are stable from week to week. Corydoras are otherwise very hardy, but in tanks with poor filtration they frequently become the first fish to get sick. This is because the bottom of the tank is the bit with the least oxygen and the worst water quality.>
I did a massive water change after the first fish died.
<Don't change more than 25% in any one day, unless you are 100% sure the new water has similar temperature, pH, and hardness.>
I was thinking of treating the whole tank with an Ick-clear product to cover my bases if its a more resistant fungus
<No, no, no... medication doesn't work this way. All you're doing is randomly adding one medicine after another. Instead, identify the disease.
Check water chemistry, water quality, and water temperature to factor out environmental issues (which cause some 90% of the fish diseases aquarists encounter). Then, if you are sure the disease requires medication, select the right medication for the job, and use precisely as instructed. Do not use more than one medication at a time, and always remove carbon (if you use it) while medicating. Don't do water changes while the course of medication is being used (this applies to those that require several doses across several days). When you're done, do two or three 25% water changes across the next couple of days to flush out any remaining medication *before* adding any new medications (or additional courses of the medication used first time around).>
Other than that I do not have any ideas, please help!
<Cheers, Neale.>
As a side note, is there any safe product to combat snails that will not kill my shrimp Also, I don't plan on replacing the 2 fish that died because I think the tank was slightly over crowded even though the water was within healthy parameters.
<See above. Never, ever add anti-snail medications to an aquarium. They do far more harm than good. Cheers, Neale.>

Corys & salt? (10/17/03) <Hi! Ananda here tonight...found one bit we hadn't really answered...> Question on the tank set-up. If I do continue with salt for my livebearers am I correct to understand that I couldn't get Panda Cory's? From what I've read they can't stand salt. <You could get panda Corys if you have a different tank for them...you won't be able to keep them in a brackish-salted tank. --Ananda>

Salt tolerance of Cory Cats 5/28/06 Hello Crew! <<Hi, Jasmine. Tom here.>> I understand that the salt tolerance of catfish in general is very poor. <<It's true that Catfish don't have a tolerance for salt at levels that other fish can tolerate quite well.>> I have some Otos, Bronze Corys and Panda Corys. <<I love these guys, Jasmine. The Pandas tend to be a little less "robust" than other Corydoras varieties but they're sure cute. :)>> For future reference when the situation eventuates, how much aquarium salt would you recommend for these fish for a) prevention of nitrite poisoning and b) disease treatment. <<Regarding (a), don't let this situation "eventuate". In a cycled tank, with proper maintenance, it simply shouldn't occur. As to (b), this isn't, unfortunately, an option because of the dosages necessary to be effective. The "cure" would be as bad as the disease, in a manner of speaking. Even with all of the benefits to be derived from the addition of aquarium salt, in your case, I'm reluctant to advise this. Neither of the instances you cite would lead me to recommend its use given that there are alternatives should the occasion arise. I hope it never does, though. ;)>> Thanks for your help! Jasmine <<Happy to, Jasmine. Tom>>

Cory With Popeye - 03/20/07 Please help me, My favorite fish is my Corydoras catfish. He recently came down with Popeye. I am not sure what type of treatment I can use for him. I've been reading online, but most of the advice is for other fish and not Cory's. I don't know their tolerance to meds. He's 7 years old. I did about a 30% water change last night. He's in a 150 gallon freshwater planted aquarium. The water is in good condition and I am not sure if he poked his eye, or what exactly happened. What would you suggest I do? I need help ASAP. I'm 25 and love fish. I know some people must think I'm nuts, but this little guy is my buddy and he needs to live. Please, can you give me some advice? Thank you. Gina <Place the sick fish in a clean hospital tank and treat with Metronidazole and Nitrofuranace.-Chuck.>
Re: Cory Cat With Popeye II 3/21/07
Okay, Where do I get that? < Local fish store or online.> Is there a certain brand? < Brand type is unimportant.> My QT tank isn't cycled. Should I take water from the main tank and place him in it with that? Please, suggestions. Thank you. < Take 50% of the water from the main tank and don't worry about the hospital tank being cycled. All you need is a heater and an airstone. Place the fish in the hospital tank with 50% new treated water. Place the fish in the tank with the medication. Do a 50% water change every day and replace with new treated water. The medications would probably kill any biological filtration and that is why an airstone is needed. After three treatments you should start to see some results.-Chuck>
Re: Help help help. Corydoras with Popeye....this fish is 7 years old. Medication Not Recommended
3/22/07 Hi Chuck. This is concerning my Cory catfish. He has Popeye. You recommended this treatment Metronidazole and Nitrofuranace. I was not able to find this at my LFS. I asked for a brand name because that is all they carry. I have PetSmart and Petco here. They do not, at least mine, do not carry that. I looked. So, I opted out and bought Maracyn. Do you think that this will help? I hope so. I love my little Cory. Let me know. Thank you. Gina <Your fish has a real problem. The medications I recommend are what work best for me. I don't think the medication you have purchased will be as effective. I believe I said that you may need to look online for these medications. Drsfostersmith.com has both of these in stock and can ship out overnight if needed. Typically these large chain stores don't carry a lot of medications.-Chuck.>

Peppered Catfish with blisters 5/28/07
Hi There <Hello.> Would love some advice <OK.> I have a Peppered Catfish (had him for approx 9 months) and he has in the past 7 days developed these water type blisters around his dorsal fin, they are see through bubble blister things!!! <"A" peppered catfish? I hope you have more than one in the tank. They are *very* sociable catfish, and the bigger the group, the better. At least keep three or four.> I have tested water all is fine as usual and PH 7. I know that they do not like salt however I do have salt in the water as they are in a community tank and they have been fine for the past 9 months. <Do not add salt. It is bad for them. Repeat after me: freshwater fish do not need salt in the water. Tonic salt is snake oil, sold to unsuspecting aquarists to extract cash from them in return for overpriced uniodized cooking salt (which is all it is). If you know they don't like salt, why are you adding some anyway?> I also have Albinos in there and they are fine along with the clown loaches maybe they are more tolerant than the Peppered? <No.> So to my questions is my catfish getting old and has a bacterial problem? <Probably not.> Will it spread to other fish? <Depends what it is. If Whitespot/Ick, then very likely yes. If simply a viral growth or tumour, then probably not. Need more of a description that "bubble blister things" to identify the problem. What's the size of the blister? Are they on the fin membrane, the spines, or the skin around the base of the fin?> What should I use to treat her? <Until you identify the problem, don't treat with anything. It's entirely possible that the salt is irritating the skin of the fish and causing physical damage, hence the blisters. So the treatment, such as it is, might well be stop adding salt and keep your catfish in a freshwater aquarium, not a brackish water one.> I have been told by a friend that salt just sits at the bottom of the tank and when you gravel vacuum you do not get rid of the salt so maybe it has become to salty and maybe burned him? <If someone was foolish enough to add the salt directly to the aquarium then yes, grains of salt could sit on the bottom of the tank. They don't "burn" the fish in any meaningful way because the fish could easily swim away from any irritant like a salt grain. But if small fish swallow whole grains of salt that would be very bad for them indeed (much as if you swallowed a whole cup of salt). Even in this worst-case scenario, the grains of salt would quickly dissolve, certainly within an hour, probably much less. Salt doesn't come out of solution again under normal aquarium conditions, so grains wouldn't "re-appear" on the substrate, so that part of your friend's story is nonsense.> I did just try to add some other Peppered and they died after a couple of days but they were very small and came from a freshwater tank at the LFS. <Quelle surprise. Please, stop adding salt to the aquarium.> Any info would be appreciated........ <Do please have a read of this article for an overview of the Corydoras group: http://www.wetwebmedia.com/FWSubWebIndex/callichthyids.htm .Peppered Corys are lovely catfish, and I've kept and bred them myself. They're essentially very hardy (mine live in a pond over summer) and very rewarding animals if treated properly. But adding salt to the Corydoras aquarium is at best pointless and at worse stressful to the fish.> Many Thanks Faye <Good luck, Neale>
Re: Peppered Catfish with blisters 5/29/07
Thanks for the input it is much appreciated, although I am finding the whole fishkeeping experience rather hilarious in the fact that there is such conflicting information. <Hello Faye. Fishkeeping is an old hobby. The Romans kept pond fish, for example, with some aristocrats spending vast sums of money on particularly fine mullets, while others gave their lampreys golden "ear-rings". Goldfish have been kept by the Chinese for hundreds of years, and the first goldfish arrived in Europe around 1700. The modern hobby started off during the Victorian era, and from about 1900 onwards steadily more and more species were kept in Europe and North America. As a result of this long time axis, masses of different methods of keeping fish have developed. Some, like the use of salt and activated carbon, are very much part of the "old" schools of thought, whereas since the 1980s, the "new" schools of thought have advocated large-scale water changes and optimizing water chemistry to match as close as possible the wild conditions. Both approaches can work, but almost without exception the "new" system works best, especially with the more delicate species. Still, you'll still find salt and carbon in the shops, and older aquarium books may even recommend them. But none of the new books do, and nor do the magazines like TFH.> I have a large aquarium near me and they have heaps of tanks both freshwater and marine. I was advised to chuck in about 5 handfuls of salt into the tank to start off with (210l tank) and then when I do water changes add just a small handful. Then people like yourself advise no salt in the water, then I read on websites that salt is great as it kills pathogens and the web site you referred me to also advises to add salt so you can see my confusion. <Salt *can* be used therapeutically. But this should be a short-term measure. Once the fish are healed, gradually remove the salt by doing water changes every few days and replacing the salty water with regular freshwater.> My Peppered Catfish (3 to start off with) always laid eggs on the glass (only to be eaten) but they were very healthy so I can only imagine that the adding of salt every water change has just become too much and maybe the one that is left has just become a bit hardier to it, but maybe the blisters are a sign that's it's too much or maybe he did eat some. having said that the Albino's are doing good and so are my Clown Loaches that are about 4 inches each. <I agree with your analysis here. How freshwater fish react to salt is difficult to predict. Some fish are more sensitive to it than others. There's very little scientific analysis of this with ornamental fish species, though goldfish have been studied in terms of salt tolerance quite a lot. In short, salt doesn't improve their health, and above a certain level, kills them.> The blisters are like a clear blister you would get on the heel of your foot if the shoes are rubbing you, they are at the base of his dorsal fin actually on the skin. There is no Ick in my tank or if there is anything the salt controls it ph is always 7 as tank is buffered. <Aquarium salt doesn't buffer the water and won't affect pH. It can't; it's sodium chloride, which doesn't buffer the water or change its pH. Marine salt mix contains other minerals that do this, various carbonate and sulphate salts in particular.> I have looked at gas bubble disease but don't really understand that too much. I have taken a photo which you may be able to see the blister is like a bubble that moves with the current and actually looks bigger today the height of the dorsal fin and possibly 5mm radius with smaller ones surrounding it. <Right, the photo is interesting. It does indeed look like gas bubble disease, though I cannot tell from the photo if the blister is filled with [a] fluid or [b] gas. Obviously if [b], then gas bubble disease. But gas bubble disease is quite rare in freshwater fish. It is caused by supersaturation of gases in the water, such as by very vigorously aerating the water. But this doesn't often happen in aquarium with regular filters and airstones. So my guess is that the blister is filled with fluid, in which case it is likely similar to a blister in humans: a mix of tissue fluid, bacteria, and dead white blood cells. Eventually it will go away by itself, but only if the fish's immune system is kept in tip-top shape. Furthermore, it's important that secondary infections such as fungus do not set in when the blister bursts. Keeping the water clean, and adding some anti-fungus/anti-Finrot remedy when the blister bursts will be important.> That's about as much as I can tell you and it is a hard hobby especially when people you think know what they are talking about (i.e. aquarium owners) give you advise to add salt then you end up with things like this. <It's really not that hard. The problem is a lot of poor information is shared, primarily because when things go wrong people just buy new fish instead of reflect on what the precise problem was. Books and magazine articles are the places to start, because they will have editorial review and likely to be fact-checked and written by real experts. Many of the writers here at WWM also write books and magazine articles (Bob Fenner and myself, for example) so you can accord us a bit of trust too. But you also should try and learn from your mistakes: if lots of your fish have died within a year, then obviously something is amiss, and you should try and figure out what's wrong before buying any more.> The other two Peppered catfish died within the past month and a half and had red patches underneath them on their tummies like some kind of haemorrhages and they couldn't swim, but did not lose any other fish and water was fine........ <Almost certainly poor water quality and/or chemistry. The red patches are bacterial infections setting in because the skin became diseases, and once the bacteria reaches the inside of the body itself, it's basically Goodnight Gracie.> From my experience (which isn't that great approx 10 months) I am getting used to the water and when it needs to be changed etc. I do a gravel vac around every 7 - 10 days. When I first started if I had a guppy sitting on bottom gulping then I would test the water and see that Ammonia was high or if my Loaches started to skip then Nitrite would be creeping up. There has been no signs like that for a while now as I am starting to get use to things and in the past if my Nitrates are up then when I gravel vac bubbles come up from the gravel all these tell tales signs have helped me learn <All sounds like you're learning. Your fishes' behaviour really can be a very good alarm bell for water quality problems. Routine helps a lot. Cleaning the gravel really shouldn't be necessary more than once a month unless you have very mess fish (or overfeed them). Simply moving the siphon over the bottom of the tank should suck up muck during water changes. I'd warmly encourage silver sand (silica sand) or volcanic sand (black sand) instead of gravel. It makes a huge difference with catfish and loaches: their behaviour is far more natural, and you watch them dig into the sand spewing out sand through the gills. Sand also tends to prevent much sinking in; instead, the muck collects on the surface where it can be easily siphoned out.> Maybe she will survive who knows. <Probably she'll be fine.> Many Thanks for your help/advice/info it is greatly appreciated and why is there so many grey areas/different opinions with fish keeping? <Partly history, as mentioned. Partly because we're still learning. Lots of aspects of the hobby are quite new, particularly in marines and with oddball freshwater fish, so information simply isn't out there.> Kind Regards Faye <Cheers, Neale>

Please can you advise ? Corydoras in trouble, no useful data 7/10/07 Dear Sir Please Could you take a look at my Albino cat fish and possible tell what could be her problem in order that I may help her or him? Thanks Keith Dean UK <This fish is either egg-bound, has a gut blockage... or some other internal complaint... W/o info. re the set-up, water quality tests, foods/feeding... et al. there is naught to do but guess as to cause here, and little to suggest re cure. I would (if the other life present can tolerate such) administer Epsom Salt... as proscribed on WWM... Please read here: http://www.wetwebmedia.com/FWSubWebIndex/saltusefaqs.htm and the linked files above. Bob Fenner>


and wrong net... Oof!

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