My corydora is sick, please help!

Fushufish

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One of my corydoras is turning white and his fins are deteriorating. I am thinking fin rot but am not sure. There are 5 other corys, one super red long fin bristle, and one angel. None of the other fish appear to have anything wrong with them. I have removed the sick Cory and am treating with erythromycin for now. Would appreciate any knowledge or advice
 

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I'm about to rip you a new one because you used anti-biotics to treat a fish that DOES NOT HAVE A BACTERIAL INFECTION. However, that should not be taken as to the behaviour of most people on this forum. Most of the people here are nice but I am sick and tired of people using anti-biotics when the fish do not have a bacterial infection.

Why do people persist in using anti-biotics when they don't know what the problem is?

Just because anti-biotics are available, it DOES NOT MEAN YOU HAVE TO USE THEM FOR EVERY LITTLE THING.

Do you take anti-biotics when you scratch yourself?
Do you take anti-biotics when you have lice or nits?
Do you take anti-biotics if you have a runny nose?

The answer should be no.

Anti-biotics should only be used as a last resort for know bacterial infections that have not responded to normal treatments. Improper use and mis-use of anti-biotics has lead to drug resistant bacteria that kill people, animals, birds, reptiles and fish.

---------------------
Now that is out of my system, your fish is covered in excess mucous that is caused by something in the water irritating the fish. It could be poor water quality, chemicals (including anti-biotics), or an external protozoan infection (costia, chilodonella or trichodina).

Test the tank water for ammonia, nitrite, nitrate and pH.

Do a 75% water change and gravel clean the substrate every day for a week or until the problem is resolved.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

If you want to add something, add some salt, (see directions below).

---------------------
SALT
You can add rock salt (often sold as aquarium salt) or swimming pool salt to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.

If you only have livebearers (guppies, platies, swordtails, mollies), goldfish or rainbowfish in the tank you can double that dose rate, so you would add 2 heaped tablespoons per 20 litres and if there is no improvement after 48 hours, then increase it so there is a total of 4 heaped tablespoons of salt per 20 litres.

Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.

The salt will not affect the beneficial filter bacteria but the higher dose rate (4 heaped tablespoons per 20 litres) will affect some plants and some snails. The lower dose rate (1-2 heaped tablespoons per 20 litres) will not affect fish, plants, shrimp or snails.

After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.

If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.

---------------------
And welcome to the forum :)

And there's no point moving the fish out of the main tank because whatever it has, is in the main tank.
 
I'm about to rip you a new one because you used anti-biotics to treat a fish that DOES NOT HAVE A BACTERIAL INFECTION. However, that should not be taken as to the behaviour of most people on this forum. Most of the people here are nice but I am sick and tired of people using anti-biotics when the fish do not have a bacterial infection.

Why do people persist in using anti-biotics when they don't know what the problem is?

Just because anti-biotics are available, it DOES NOT MEAN YOU HAVE TO USE THEM FOR EVERY LITTLE THING.

Do you take anti-biotics when you scratch yourself?
Do you take anti-biotics when you have lice or nits?
Do you take anti-biotics if you have a runny nose?

The answer should be no.

Anti-biotics should only be used as a last resort for know bacterial infections that have not responded to normal treatments. Improper use and mis-use of anti-biotics has lead to drug resistant bacteria that kill people, animals, birds, reptiles and fish.

---------------------
Now that is out of my system, your fish is covered in excess mucous that is caused by something in the water irritating the fish. It could be poor water quality, chemicals (including anti-biotics), or an external protozoan infection (costia, chilodonella or trichodina).

Test the tank water for ammonia, nitrite, nitrate and pH.

Do a 75% water change and gravel clean the substrate every day for a week or until the problem is resolved.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

If you want to add something, add some salt, (see directions below).

---------------------
SALT
You can add rock salt (often sold as aquarium salt) or swimming pool salt to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.

If you only have livebearers (guppies, platies, swordtails, mollies), goldfish or rainbowfish in the tank you can double that dose rate, so you would add 2 heaped tablespoons per 20 litres and if there is no improvement after 48 hours, then increase it so there is a total of 4 heaped tablespoons of salt per 20 litres.

Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.

The salt will not affect the beneficial filter bacteria but the higher dose rate (4 heaped tablespoons per 20 litres) will affect some plants and some snails. The lower dose rate (1-2 heaped tablespoons per 20 litres) will not affect fish, plants, shrimp or snails.

After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.

If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.

---------------------
And welcome to the forum :)

And there's no point moving the fish out of the main tank because whatever it has, is in the main tank.
Thank you for your advice, lol even the stern advice is appreciated. The water chemical levels (nitrate, nitrite, ammonia, and pH) are all balanced and as they should be. I agree to not be hasty with antibiotics, they were recommended from fish store and out of fear that my fish would die I probably reacted hastily.
Now that the damage has been done and my fish is separated and in a quarantine tank with Rx, should I take him out and move him back into the Community tank and continue with your recommended treatment? Also, is the excess mucous also the cause of the fins deteriorating so dramatically? Appreciate the guidance! Thank you!
 
I'm about to rip you a new one because you used anti-biotics to treat a fish that DOES NOT HAVE A BACTERIAL INFECTION. However, that should not be taken as to the behaviour of most people on this forum. Most of the people here are nice but I am sick and tired of people using anti-biotics when the fish do not have a bacterial infection.

Why do people persist in using anti-biotics when they don't know what the problem is?

Just because anti-biotics are available, it DOES NOT MEAN YOU HAVE TO USE THEM FOR EVERY LITTLE THING.

Do you take anti-biotics when you scratch yourself?
Do you take anti-biotics when you have lice or nits?
Do you take anti-biotics if you have a runny nose?

The answer should be no.

Anti-biotics should only be used as a last resort for know bacterial infections that have not responded to normal treatments. Improper use and mis-use of anti-biotics has lead to drug resistant bacteria that kill people, animals, birds, reptiles and fish.

---------------------
Now that is out of my system, your fish is covered in excess mucous that is caused by something in the water irritating the fish. It could be poor water quality, chemicals (including anti-biotics), or an external protozoan infection (costia, chilodonella or trichodina).

Test the tank water for ammonia, nitrite, nitrate and pH.

Do a 75% water change and gravel clean the substrate every day for a week or until the problem is resolved.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

If you want to add something, add some salt, (see directions below).

---------------------
SALT
You can add rock salt (often sold as aquarium salt) or swimming pool salt to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.

If you only have livebearers (guppies, platies, swordtails, mollies), goldfish or rainbowfish in the tank you can double that dose rate, so you would add 2 heaped tablespoons per 20 litres and if there is no improvement after 48 hours, then increase it so there is a total of 4 heaped tablespoons of salt per 20 litres.

Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.

The salt will not affect the beneficial filter bacteria but the higher dose rate (4 heaped tablespoons per 20 litres) will affect some plants and some snails. The lower dose rate (1-2 heaped tablespoons per 20 litres) will not affect fish, plants, shrimp or snails.

After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.

If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.

---------------------
And welcome to the forum :)

And there's no point moving the fish out of the main tank because whatever it has, is in the main tank.
Thank you for your advice, lol even the stern advice is appreciated. The water chemical levels (nitrate, nitrite, ammonia, and pH) are all balanced and as they should be. I agree to not be hasty with antibiotics, they were recommended from fish store and out of fear that my fish would die I probably reacted hastily.
Now that the damage has been done and my fish is separated and in a quarantine tank with Rx, should I take him out and move him back into the Community tank and continue with your recommended treatment? Also, is the excess mucous also the cause of the fins deteriorating so dramatically? Appreciate the guidance! Thank you!
Did you see the photo of his fins deteriorating? Also I am pretty anal about the water levels so I check them probably more than most and they are never out of whack. I do not add any chemicals to the tank except for conditioner for the new water that is added. What are some other reasons could be causing this? How can I check for parasites? My fish are like my babies, I just want them to be safe and healthy and happy ???
 
Q
One of my corydoras is turning white and his fins are deteriorating. I am thinking fin rot but am not sure. There are 5 other corys, one super red long fin bristle, and one angel. None of the other fish appear to have anything wrong with them. I have removed the sick Cory and am treating with erythromycin for now. Would appreciate any knowledge or advice
I am thinking it could be a fungal infection. Most likely caused by poor water quality.
 
For Fushufish.
I have to appologise for my original thread. I was kept up all night by the neighbours dog barking and the council hasn't done anything about it even though it's been going on for 4 years. That combined with too many people using anti-biotics in tanks when they have no idea what is wrong with the fish. I don't blame you for buying the medication, I blame the shops that sell anti-biotics to anyone when they don't know what is wrong with the fish. Any way, I'm sorry, I shouldn't have gone off because you didn't deserve it.

--------------------
This is not a fungal infection (aka fungus).

The fins can be damaged by external protozoa that chew the skin and fins.

You can either treat the fish with salt in the quarantine tank or put it back in the main tank. Corydoras prefer company so I would move it back to the main tank and treat that, rather than leaving it on its own.

--------------------
All fish have a thin layer of clear mucous over their body and fins. It helps them move through the water easier and offers a line of protection against poor water quality and disease organisms. If the fish is stressed by something in the water, it produces more mucous and that appears as a cream, white or grey film over the body and fins.

If the cream, white or grey film is in patches on the body, it is usually from external protozoan parasites.

If the entire body, fins, head and eyes are covered in a cream, white or grey film, it is usually poor water quality or chemicals irritating the fish.

The fish in the picture has excess mucous over its body and dorsal (top) fin but the head is clear, this suggests external protozoa.
 
For Fushufish.
I have to appologise for my original thread. I was kept up all night by the neighbours dog barking and the council hasn't done anything about it even though it's been going on for 4 years. That combined with too many people using anti-biotics in tanks when they have no idea what is wrong with the fish. I don't blame you for buying the medication, I blame the shops that sell anti-biotics to anyone when they don't know what is wrong with the fish. Any way, I'm sorry, I shouldn't have gone off because you didn't deserve it.

--------------------
This is not a fungal infection (aka fungus).

The fins can be damaged by external protozoa that chew the skin and fins.

You can either treat the fish with salt in the quarantine tank or put it back in the main tank. Corydoras prefer company so I would move it back to the main tank and treat that, rather than leaving it on its own.

--------------------
All fish have a thin layer of clear mucous over their body and fins. It helps them move through the water easier and offers a line of protection against poor water quality and disease organisms. If the fish is stressed by something in the water, it produces more mucous and that appears as a cream, white or grey film over the body and fins.

If the cream, white or grey film is in patches on the body, it is usually from external protozoan parasites.

If the entire body, fins, head and eyes are covered in a cream, white or grey film, it is usually poor water quality or chemicals irritating the fish.

The fish in the picture has excess mucous over its body and dorsal (top) fin but the head is clear, this suggests external protozoa.

I had a similar issue with my two remaining cories a few weeks ago, and it made me super nervous because I lost a lot of cories from the same group and threw everything under the sun at them treatment wise to try and save them.

so I had two survivors and now they had some white stuff on their heads, caudal fins and tails.

before I went to using salt, I did everything I could to keep my water quality in check. (Turns out I think my use of meds actually killed some of my bacteria and I was in the middle of a crashed cycle, one point for Colin Ts

I managed to get my water back up to par, kept the tank clean and the cories recovered with little to no signs of stress apart from the small coating they had. Which in hind sigh appears to be what is happening with the OP’s fish.

I did not even resort to salt.

you can only read so many times it’s not a good idea to treat a tank for infections that might not be there. There is something to be said also for ignoring that instinct and just buckling down with some hard work.

making sure your water quality is better than good should and is the best first step. Worked for me.
 
I had a similar issue with my two remaining cories a few weeks ago, and it made me super nervous because I lost a lot of cories from the same group and threw everything under the sun at them treatment wise to try and save them.

so I had two survivors and now they had some white stuff on their heads, caudal fins and tails.

before I went to using salt, I did everything I could to keep my water quality in check. (Turns out I think my use of meds actually killed some of my bacteria and I was in the middle of a crashed cycle, one point for Colin Ts

I managed to get my water back up to par, kept the tank clean and the cories recovered with little to no signs of stress apart from the small coating they had. Which in hind sigh appears to be what is happening with the OP’s fish.

I did not even resort to salt.

you can only read so many times it’s not a good idea to treat a tank for infections that might not be there. There is something to be said also for ignoring that instinct and just buckling down with some hard work.

making sure your water quality is better than good should and is the best first step. Worked for me.
Everyone keeps going back to water quality but literally my water quality is PERFECT. I test it regularly and there has never even been a slight deviance in its balanced quality ever since it cycled completely. I even bought an all new testing kit in case for some reason my testing agents had turned but the new kit retained the same results! It’s so baffling to me because of course my first thought was water quality. In my angel’s last tank I was having a lot of issues with pH and Ammonia variance so I am pretty OCD about it these days. I am taking into account all the information here and hoping Haans starts to look better over the next couple days. Thank you for your input and relaying your experience!
 
Did you see the photo of his fins deteriorating? Also I am pretty anal about the water levels so I check them probably more than most and they are never out of whack. I do not add any chemicals to the tank except for conditioner for the new water that is added. What are some other reasons could be causing this? How can I check for parasites? My fish are like my babies, I just want them to be safe and healthy and happy ???
For Fushufish.
I have to appologise for my original thread. I was kept up all night by the neighbours dog barking and the council hasn't done anything about it even though it's been going on for 4 years. That combined with too many people using anti-biotics in tanks when they have no idea what is wrong with the fish. I don't blame you for buying the medication, I blame the shops that sell anti-biotics to anyone when they don't know what is wrong with the fish. Any way, I'm sorry, I shouldn't have gone off because you didn't deserve it.

--------------------
This is not a fungal infection (aka fungus).

The fins can be damaged by external protozoa that chew the skin and fins.

You can either treat the fish with salt in the quarantine tank or put it back in the main tank. Corydoras prefer company so I would move it back to the main tank and treat that, rather than leaving it on its own.

--------------------
All fish have a thin layer of clear mucous over their body and fins. It helps them move through the water easier and offers a line of protection against poor water quality and disease organisms. If the fish is stressed by something in the water, it produces more mucous and that appears as a cream, white or grey film over the body and fins.

If the cream, white or grey film is in patches on the body, it is usually from external protozoan parasites.

If the entire body, fins, head and eyes are covered in a cream, white or grey film, it is usually poor water quality or chemicals irritating the fish.

The fish in the picture has excess mucous over its body and dorsal (top) fin but the head is clear, this suggests external protozoa.
This is Fin rot. The entire fin is gone.
whoever says for confidence that there is no role for antibiotics in fin rot, needs to check pathophysiology of fin rot and have to be more open to all etiologies of fin rod. Even a parasitic infection leads to secondary bacterial infection. Antibiotics is appropriate. Salt is appropriate. And temporarily treating the fish in hospital tank is also appropriate.
 
Try salt for a week and see if it helps. If it doesn't then look for a broad spectrum fish medication. But salt will treat external protozoan infections, which probably contributed or caused the damage to the dorsal fin. Salt also treats minor bacterial and fungal infections, which is why it should be the first choice, along with a big water change and gravel clean. The water changes and gravel cleaning dilute the number of disease organisms in the tank and provide a cleaner environment for the fish to be treated in and recover in.
 
This is Fin rot. The entire fin is gone.
whoever says for confidence that there is no role for antibiotics in fin rot, needs to check pathophysiology of fin rot and have to be more open to all etiologies of fin rod. Even a parasitic infection leads to secondary bacterial infection. Antibiotics is appropriate. Salt is appropriate. And temporarily treating the fish in hospital tank is also appropriate.
I agree that it looks like textbook fin rot!
 
Try salt for a week and see if it helps. If it doesn't then look for a broad spectrum fish medication. But salt will treat external protozoan infections, which probably contributed or caused the damage to the dorsal fin. Salt also treats minor bacterial and fungal infections, which is why it should be the first choice, along with a big water change and gravel clean. The water changes and gravel cleaning dilute the number of disease organisms in the tank and provide a cleaner environment for the fish to be treated in and recover in.
 

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