Cory Cats -- Need Help Diagnosing Disease/treatment

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Jonathan Greenberg

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Hi there -- my cory cats have had a faint white film on them for a month or so now. I recently learned it was likely a fungal disease, and just completed my first week of Pimafix/Melafix treatment. A few days after the treatment began, one of the Cory's developed this clump on its side (it wasn't there before).

Is this the fungus dying, or is it expanding? Thoughts/treatments?
 

Swampgorilla

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Honestly ... I know a lot of folks swear by them ... but I really don't think Pimafix and Melafix are "all that". I don't think they're harmful, mind you, and might even do some good but I don't believe they have "curing" properties. More like symptom treatment if you ask me.

Is your water good? Ammonia / Nitrite ... O? Nitrates? Well, for corys I keep mine at 0 too.

Corys are sensitive fish and can have bad reactions to certain meds ... so treating them without knowing the root cause is a bit hazardous. Although I would agree your problem looks FUNGAL ... it could also be bacterial.

I notice you have gravel ... I switched away from gravel to sand specifically because I had bacterial and fungal problems with my corys. It's impossible to keep gravel clean and bacteria free.

Try the GOOD WATER route. If you've already done it - you may have to up the game to real meds but, again ... with corys it's a last resort for me.
 
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Jonathan Greenberg

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Ammonia/Nitrite 0 always, Nitrates hover around 20-40ppm (EI dosing of a planted tank) -- the tank is high tech so I do have CO2 injections, so the water tends to be more acidic (pH 6.6 or so depending on the time of day). I do weekly 50% changes (today is the last day of the treatment so I'll do a 50% change tomorrow) due to the EI dosing regimen. I did previously have a pretty bad outbreak of BGA but its been knocked out via an Ultralife dosing.

It looks like (at least) one of my Bristlenose Pleco has a tad bit of fungus as well (the fungus is really pale so it was hard to see on that fish).

It just occurred to me that I think I have carbon filters in my eheim -- would that more or less negate the effects of the Pimafix? Worth doing a 2nd round of treatment without the carbon?
 

TexasDomer

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Pimafix and Melafix are useless - not worth doing another round.

What do you feed them?

Do they have their barbels?

Can you give tank size and complete stocking? Temp?
 
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Jonathan Greenberg

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Tetramin tropical crisps, yep all have their barbels, current stock:


Edit: 75 degree tank!
 

TexasDomer

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You have stocking issues if you'd like to discuss them

For the cories, I'm not sure what could be causing it. I would try to increase your water changes (I know, not good for the EI dosing - do you have a QT tank you can move the fish to?).
 
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Jonathan Greenberg

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No QT. I can certainly increase water changes. Are there no other treatments that may work?

What's the problem with the stocking? I figured with the plants I could get a little over my normal stocking (but according to the website I'm not too far over the stocking level).
 

TexasDomer

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I wouldn't throw meds at the problem without knowing what it is. Often fungal infections are secondary to bacterial infections, so just treating the fungal issue wouldn't treat the underlying issue. I also wouldn't add meds to your whole tank. I'd purchase a QT tank (a 10 gal from the Petco $1/gal sale would be perfect, then get a cheap air pump and a sponge filter) and QT him before treating.

Stocking websites like Aqadvisor aren't accurate. They don't take into account of lot of things (behavior, aggression, diet), and they have some bad info on water parameters for some species.

I think you have too many schooling species for a 36" tank - 2 schools in the upper/mid levels of the tank is a good max for tanks 4 ft and under. You have 4 schooling species (danios, neons, two rainbows).

Cories should be in larger groups of their own species - keeping them in smaller groups can be stressful, and stress can increase susceptibility to disease. However, Sterbai don't have a lot of temperature overlap with the other species in the tank, and I would recommend a different cory species to go with the cool water schooling fish you've chosen. 75 F is the extreme low for Sterbai, and it's not recommended to keep fish at the extreme ends of their temp ranges - also stressful.

Are both dwarf gouramis male?
 
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Jonathan Greenberg

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Thanks. I'll consider getting a QT tank. Pima/Melafix are tree teas, right? Is there any worry about the fishies in the tank if I dose the entire tank? The only things I've read that are a minor concern are the Gouramis, but it seems correlative and no evidence of causative with the effects of those treatments on labyrinth fish. I did remove the carbon filter -- I had it in during the first round of dosing so I'm going to see if a 2nd week + no carbon works.

Re: stocking and water parameters -- what would you consider accurate and a good site to see these sort of issues? In terms of temperatures, I've seen sites that say Sterbais are happy from 70 to 77, so 75 is not towards an extreme, and others that put 75 at the bottom of their happy range. Here's a small assortment of different temperature ranges -- how to choose which one is "right"?

Also, the rainbows stay at the top, the tetras at the bottom, and the danios NEVER school in my tank -- they occupy all levels of my tank (it is approaching "heavily planted" on 1/2 of the volume of the tank -- I have ~ 1/2 fairly open). Given this, are there still issues with schooling? All the fish seem pretty happy and can get away from one another if need be.

Gouramis I'm not sure about -- I noticed one tends to hide a lot towards the bottom and back of the tank and the other likes to be out front and get under my floating plants.
 
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Jonathan Greenberg

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Sorry, I didn't mean this to come off as argumentative, I'm just trying to work through the problem. It seems you are suggesting to first figure out the root causes. It seems it could be:
1) Nothing -- fungus happens.
2) Temperature extremes (arguable given various online sources)
3) Not enough conspecifics leading the stress (possible, but I can't imagine just adding new corys will solve the short term problem and may lead to more vectors for the fungus)
4) Water quality issues (40 ppm nitrates too high?) -- I'm going to back off on my EI macros just in case.

I'm pretty sure this is a fungal problem -- do you agree with that? The fishes are otherwise healthy looking (to be clear 2/3 corys have the white filmy stuff, the other one has nothing -- the picture is the one with the more clumped patch, the other one has a faint film around its head) -- no ripped fins, active swimming, good appetite. Besides water quality, what is the next course of action in terms of medication (QT tank or not -- what is the recommended way to remove fungus from this fish)?
 

TexasDomer

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Jonathan Greenberg said:
Thanks. I'll consider getting a QT tank. Pima/Melafix are tree teas, right? Is there any worry about the fishies in the tank if I dose the entire tank? The only things I've read that are a minor concern are the Gouramis, but it seems correlative and no evidence of causative with the effects of those treatments on labyrinth fish. I did remove the carbon filter -- I had it in during the first round of dosing so I'm going to see if a 2nd week + no carbon works.

They're diluted herbal remedies that really won't do much. It's a waste of your money to use them. Because there have been some reports of it harming labyrinth fish (even correlative), I wouldn't risk it, especially since there's no reward expected from it's use.

Re: stocking and water parameters -- what would you consider accurate and a good site to see these sort of issues? In terms of temperatures, I've seen sites that say Sterbais are happy from 70 to 77, so 75 is not towards an extreme, and others that put 75 at the bottom of their happy range. Here's a small assortment of different temperature ranges -- how to choose which one is "right"?

LiveAquaria is inaccurate, and the Fishlore profiles are often inaccurate with old info. I use Seriously Fish and Fishbase for non-catfish, and Planet Catfish as the main source for catfish. Check out Planet Catfish's recommendation for them - I would go with that one (if I recall correctly, it's very similar to Seriously Fish's recommendation).

Also, the rainbows stay at the top, the tetras at the bottom, and the danios NEVER school in my tank -- they occupy all levels of my tank (it is approaching "heavily planted" on 1/2 of the volume of the tank -- I have ~ 1/2 fairly open). Given this, are there still issues with schooling? All the fish seem pretty happy and can get away from one another if need be.

Yes, I think you have too many species for this size tank. Larger groups of fewer species is usually preferred by schooling fish.

Gouramis I'm not sure about -- I noticed one tends to hide a lot towards the bottom and back of the tank and the other likes to be out front and get under my floating plants.

Yep, sounds like one is bullying the other into hiding. I'd rehome one of them - two male DGs rarely works out, even in larger tanks, and you could come home to one injured or dead from fighting. Even without physical aggression, the stress from bullying can starve one, or make him more likely to get sick. Not a fair life for him.
Jonathan Greenberg said:
Sorry, I didn't mean this to come off as argumentative, I'm just trying to work through the problem. It seems you are suggesting to first figure out the root causes. It seems it could be:
1) Nothing -- fungus happens.
2) Temperature extremes (arguable given various online sources)
3) Not enough conspecifics leading the stress (possible, but I can't imagine just adding new corys will solve the short term problem and may lead to more vectors for the fungus)
4) Water quality issues (40 ppm nitrates too high?) -- I'm going to back off on my EI macros just in case.

Yes, though sometimes we can't figure out the problem and have to go with our best guess. But fungus just doesn't happen - usually it's secondary to bacterial infections or it can become a problem in immunocompromised fish, and often fish are immunocompromised because of stress. Temperature stress (though I'm not convinced that's the major factor here) and stress from being in too small of a group can both negatively affect the fish's health and ability to fight off diseases. Fungus usually does not infect healthy fish, so adding more cories wouldn't necessarily increase the disease in the tank. If they're not stressed or sick, it shouldn't be a problem for them.

40 ppm nitrates is high, but not alarmingly so. Lower would be better. If you have such high nitrates, I would guess that macros are not a problem for you, and reducing your macro dosing should be okay. I would try to keep nitrates under 20 ppm.

I'm pretty sure this is a fungal problem -- do you agree with that? The fishes are otherwise healthy looking (to be clear 2/3 corys have the white filmy stuff, the other one has nothing -- the picture is the one with the more clumped patch, the other one has a faint film around its head) -- no ripped fins, active swimming, good appetite. Besides water quality, what is the next course of action in terms of medication (QT tank or not -- what is the recommended way to remove fungus from this fish)?

Fungal, possibly. Could also be bacterial as the primary infection, with fungal secondary, or it could just be bacterial - some bacterial infections look fuzzy like fungal. If it's the latter two, treating with an antifungal med won't be helpful in treating the underlying cause.

I'm sorry I can't give you more definitive answers, but that's where we are with fish medicine - people can rarely accurately diagnose the issue, and trying meds and hoping for a good outcome is where we are. This is why I stress so much the importance of proper stocking and pristine water quality - sometimes fixing these issues can help the fish fight off the issue without meds (less stress, better immune function), and at the very least, fixing these issues can help prevent future issues as well.

If it were my tank, I'd increase water changes in the main tank, rehome the rainbows, QT the cories (with a thin layer of sand in the QT tank - bare bottom can be problematic for them), start with daily water changes in the QT tank, and treat with something like methylene blue (not to be used in the main tank, it'll stain your silicone and decor). After the Sterbai are healthier, I'd return them and get 6-8 individuals of a cory species that is temperature compatible with the neons and the danios.
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