Mystery disease killing Corydoras, need help

[TGK]

Looking for advice on how to treat this disease that is currently affecting my Panda Corydoras. 

 

I originally couldn't identify it as a fungus or bacterial, so I followed advice from Aquarium Coop and began treating both with Ich-X (for the anti-fungal properties) and Erithromycin for the anti-bacterial. It's been three days so far, and the disease appears to just continue to progress and spread. It appears this morning that two more Corydoras are now showing symptoms. 

 

Can anyone ID what disease this is, and how it should be treated? 

[TGK]

Here are more close-up pictures, which might help identification: 

[Andrew]

I would lean on this being a fungus, but as I am no expert myself I would wait for someone else to also come to that conclusion. What I would recommend in the meantime is moving the affected fish to a quarantine tank, if possible, and following the salt treatment guideline provided by one of aquarium coops blog articles (https://www.aquariumcoop.com/blogs/aquarium/aquarium-salt-for-sick-fish). If that doesn't work and your current medications also appear to not do anything, I would suggest switching to medications with other types of active ingredients (so no maracyn, as that contains erythromycin, and avoid ich-x's active ingredient of malachite green). I hope others here may be able to better narrow down the disease for you and I hope your fish do better!

[Kat_Rigel]

My gut also says its a fungus. The growth really makes me think thats it. I second Andrew's advice.

[TGK]

So I've ordered some aquarium salt but my understanding was that it couldn't be used in planted tanks. I currently don't have a cycled hospital tank to move the affected Corydoras into. 

 

Is there a known dosing guideline for planted tanks specifically? 

 

Also, if it is a fungus, is there a recommended treatment that is invert/plant safe? 

[ange]

Ich-X is a plant-safe antifungal. If you're running a sponge filter in your planted tank you can transfer it to a hospital tank and wait a couple of days to make sure that your BB are still alive and your quarantine tank is cycled. Some people run an extra sponge filter for this purpose. You can also use filter media from your main tank to try cycling a quarantine tank quickly, but personally I have best results with transferring a sponge filter between tanks.

Personally I wouldn't dose any salt in a planted tank. If you aren't able to cycle a quarantine tank, I'd suggest salt dipping your corys rather than quarantining them with salt.

[Kat_Rigel]

Agreed, I would avoid salt in a planted tank and would use ich-x to treat the tank. Small disclaimer: havent used ich-x before, but I have never seen anything that would make me avoid it.

You can set up a makeshift hospital tank very easily. Use a plastic tote from a hardware store, dollar store, etc- its not pretty like a glass aquarium, but it does the job. If you dont have an extra cycled sponge filter or media to put in the hospital "tank," try to at least put something in there that has biofilm- a rock, a decoration, etc. Personally I would take at least a small amount of the filter media from my regular tank and place it in tbe hospital tank (assuming you have a HOB filter or similar.)

[TGK]

My aquarium salt has just arrived, might attempt to do a salt bath tonight. I've heard that Corydoras are especially sensitive to salt, any recommendations for how to perform the salt bath (i.e., for how long, and at what concentration of salt?) 

 

 

[Ben Ellison]

I have ran a tablespoon  per 10 gallons with no noticeable  effect on my plants or Cory's. I know the normal  amount recommended  for sick fish is to start with 1 tablespoon  per gallon. This video should  be helpful

 

[TGK]

Update: 

Corydoras have begun to die off; I really don't think that the combination of Erithromycin + Ich-X is doing anything. Disease appears to keep progressing day by day. 

 

Can anyone positively ID what disease this is? I fear if I just treat at random with another ineffective med I'm going to lose all of my Corydoras to whatever this thing is. Things are getting pretty urgent. 

 

Also scared of dosing salt because I have snails + plants and don't want to cause a die off that will deteriorate water quality. 

[Tre]

Corys are scaleless fish and Ich-x must be used in half doses to not kill them.... goes for all catfish... use salt instead to be safe.

[Tre]

I would move them to a hospital tank and use salt for a few days....that way you're not wrecking the whole tank.  Just grab an extra small tank or even an XL kritter keeper.

[TGK]

I've went and acquired a 10-gallon to act as a hospital tank and removed the 5 Corydoras that are affected by whatever disease this is and placed them in the tank.

 

I've dosed salt at a level of 1 tbsp per 3 gallons. 

 

Should I continue dosing Erithromycin as well (fins are rotting away on a few affected cories). 

 

Also, how high of a salt concentration is safe to use with corydoras? I assume the 1 tbsp per gallon wouldn't be tolerated? 

[ange]

Salt dosage really varies with what your water is like but generally speaking 1tbs/3 gallons will be safe for most species. If your corys don't show signs of improvement with this dosage I'd suggest either upping the salinity or using a different medication.

I've got no experience using meds in conjunction with salt so can't really speak for whether it's a good idea or not.

[TGK]

Corydoras have been in hospital tank with salt for about two days. Not seeing major improvements, white growths may have advanced a bit, but it's hard to tell. Two Corydoras now have had their fins almost entirely eroded off. 

 

Advice? Do I up the salinity? Start adding in Erithromycin with the salt? 

[Mmiller2001]

3 hours ago, TGK said:

Corydoras have been in hospital tank with salt for about two days. Not seeing major improvements, white growths may have advanced a bit, but it's hard to tell. Two Corydoras now have had their fins almost entirely eroded off. 

 

Advice? Do I up the salinity? Start adding in Erithromycin with the salt? 

You might try this. They market it as "I don't know what disease is happening". Worth a shot if you can get it in time. https://www.seachem.com/sulfaplex.php

[MattyIce]

 

On 9/16/2020 at 8:24 PM, TGK said:

Can anyone positively ID what disease this is? I fear if I just treat at random with another ineffective med I'm going to lose all of my Corydoras to whatever this thing is. Things are getting pretty urgent. 

Not sure but it looks like Columnaris.

[TGK]

Hi all, wanted to update this post as I've been able to save the remaining 5 diseased Corydoras and wanted to share my experience. 

Disease Description: Disease would initially present itself as a small patch of white/grey film on the tail area of the Panda Corydoras, then rapidly spread over the entire body. When it spread to the fins, the fins would rapidly erode. 

Potential Cause: This disease appeared in my aquarium after an unprecedented cold front where the temperature in the tank dropped from about 78 to 68-70 for 2-3 days. I think this is what caused it, as well as a gunked up filter that wasn't operating at full capacity. 

Treatment Timeline:

• Day 1 - Noticed a slight discoloration on the tail of one Panda Corydoras, but all other Corydoras looked fine and were active/eating so I didn't think much of it. 
• Day 2 - Initial Corydoras deteriorated rapidly with quite a large portion of the tailfin being eroded within 24 hours. I begin dosing with Ich-X and Erithromycin. 
• Days 3-6 - Kept dosing with Ich-X and Erithromycin, the Ich-X noticeably irritates the Corydoras and makes them constantly dart up for gulps of air. Treatment doesn't seem to be having any effect, and by this point the disease has spread to 6 Corydoras, and they're deteriorating rapidly. I'm asking for advice online by this point. One Corydoras has died at this point. 
• Day 7 - Bought a 10 gallon hospital tank, and set it up with a sponge filter (from main aquarium) and about a dozen miniature Catappa leaves. I dose 10 teaspoons of salt at this point (around 3 tbsp per 10 gal), and add the remaining 5 affected Corydoras after tearing apart the main aquarium. 
• Day 8 - Notice that one Corydoras in the main aquarium that wasn't removed the day before also exhibiting the beginning signs of symptoms (see image 1 attached). Don't have time to tear apart the aquarium, so I leave it in the tank. 
• Day 9 - Corydoras inside the hospital tank continue to deterioriate (see attached pictures 2-3), so slowly over 24h I increase the salt concentration to 4 tbsp per 10 gallons. At this point, I begin noticing signs of stress in the Corydoras (flashing, erratic swimming) so I stop adding salt. 
• Day 10 - All 5 Corydoras in the hospital tank have eroded fins and white growths over the body, so I begin medicating with Erithromycin because I figure that some type of bacterial infection would be at play with the open sores/eroded tails. 
• Days 11-14 - Erithromycin dosed each day, salt is kept constant at 4 TBSP per 10 gal. I feed Xtreme nano pellets to the Corydoras 2x per day. Corydoras will not touch any other food besides the Xtreme nano. 
• Day 15 - After 5 days of Erithromycin I did a 30% water change, and didn't replace the salt (so now back to around 3 tbsp per gallon). Only one Corydoras remains with white growths on the body, other Corydoras are showing signs of regrowth in the tails (see picture 4). Corydoras in the main tank is thankfully healed on its own without medication and hasn't spread the disease. 
• Day 17 - Did another 30% water change without replacing salt. Still have 1 Corydoras with slight growths on its body, but appears to continue to be improving. (See last picture attached). 

 

In the end, I suspect it was a bacterial disease because the combination of Erithromycin + salt seemed to work out the best. Corydoras seemed to continue to deteriorate with just salt / just Erithromycin alone. 

Also as a note, the Ich-X really seemed to be extremely harsh on the Corydoras and I think I'll be much more careful about dosing it with Corydoras going forward. I was dosing it because I wasn't sure if the disease was bacterial or fungal. Honestly, I think that the 1 Corydoras that I lost during this whole process might not have died if I hadn't dosed Ich-X, because that particular corydoras was noticeably stressed after dosing that med. 

Thanks again to all for the advice/feedback. 

 

Edited September 26, 2020 by TGK

[breamonster]

Thank you so much for sharing such a thorough account of your experience. I have a panda that has the exact same thing going on.