Sick Corydoras

aposh · Dec 16, 2021

My trilineatus corydoras catfish are dying off. I had 2 die about 3 weeks ago and I think another one may die very soon. He seemed to have a split fin on his underside, a small hole in one of his front side fins, and some sort of white growth on his small back dorsal fin. I thought maybe fin rot, but what has been throwing me off is that all three of the catfishs’ first symptoms was that they couldn’t hold themselves complexly upright. They would tip onto their sides for a few weeks, and then laid on their sides when it got worse. Does anyone know what this might be/have any tips? I have 4 other corydoras, and I want to keep them healthy.

Naughts · Dec 16, 2021

What are the tank conditions and parameters? How long has the tank been running? What size is the tank?

aposh · Dec 16, 2021

Tank is 20 gallon long. Ammonia levels are 0 ppm. I keep the tank at about 74-76 ish degrees Farenheit (~24 Celsius). I had a tank set up for a few years, and then last year around this time I switched over to the 20 gallon when I dirted it, but kept the same filter media, gravel, decorations, plants, etc. I have an otocinclus that I’ve had for probably over 8 years, and I also have a baby molly that has been living in the tank for 7 months.

Naughts · Dec 16, 2021

Conditions sound good. Often fin damage is a secondary infection.

Do you think the gills look pink? Any damage to the barbels?

Are they eating well and does the poo look normal?

aposh · Dec 16, 2021

Naughts said:
Conditions sound good. Often fin damage is a secondary infection.

Do you think the gills look pink? Any damage to the barbels?

Are they eating well and does the poo look normal?

Yes, gills were pink on the other 2 earlier and this one as well. The fins look normal color to me. The barbels do not look damaged, but the very first one that died did have some barbel and mouth damage, if that helps. The other ones seem to be eating well but I doubt this one is because he cannot swim or sit upright. He mainly has been laying on his side. I think their poo is normal, but I am not 100% sure

itiwhetu · Dec 16, 2021

What is the pH of your tank.

Colin_T · Dec 17, 2021

aposh said:
Tank is 20 gallon long. Ammonia levels are 0 ppm. I keep the tank at about 74-76 ish degrees Farenheit (~24 Celsius).

What is the nitrite, nitrate and pH of the tank water?

Have you added anything new to the tank in the 2 weeks before this started?

-------------------
The fish looks like it is covered in excess mucous, which is normally caused by poor water quality or something in the water irritating the fish.

Wipe the inside of the glass down with a clean fish sponge. This removes the biofilm on the glass and the biofilm will contain lots of harmful bacteria, fungus, protozoans and various other microscopic life forms.

Do a 75% water change and gravel clean the substrate every day for a week. The water changes and gravel cleaning will reduce the number of disease organisms in the water and provide a cleaner environment for the fish to recover in. It also removes a lot of the gunk and this means any medication can work on treating the fish instead of being wasted killing the pathogens in the gunk.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.

Clean the filter if it hasn't been done in the last 2 weeks. However, if the filter is less than 6 weeks old, do not clean it. Wash the filter materials/ media in a bucket of tank water and re-use them. Tip the bucket of dirty water on the garden/ lawn. Cleaning the filter means less gunk and cleaner water with fewer pathogens.

Increase surface turbulence/ aeration to maximise the dissolved oxygen in the water.

If there's no improvement after a clean and a few water changes, post more pictures of all the fish. A short (1 minute) video might show something too.

aposh · Dec 17, 2021

Colin_T said:
What is the nitrite, nitrate and pH of the tank water?

Have you added anything new to the tank in the 2 weeks before this started?

-------------------
The fish looks like it is covered in excess mucous, which is normally caused by poor water quality or something in the water irritating the fish.

Wipe the inside of the glass down with a clean fish sponge. This removes the biofilm on the glass and the biofilm will contain lots of harmful bacteria, fungus, protozoans and various other microscopic life forms.

Do a 75% water change and gravel clean the substrate every day for a week. The water changes and gravel cleaning will reduce the number of disease organisms in the water and provide a cleaner environment for the fish to recover in. It also removes a lot of the gunk and this means any medication can work on treating the fish instead of being wasted killing the pathogens in the gunk.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.

Clean the filter if it hasn't been done in the last 2 weeks. However, if the filter is less than 6 weeks old, do not clean it. Wash the filter materials/ media in a bucket of tank water and re-use them. Tip the bucket of dirty water on the garden/ lawn. Cleaning the filter means less gunk and cleaner water with fewer pathogens.

Increase surface turbulence/ aeration to maximise the dissolved oxygen in the water.

If there's no improvement after a clean and a few water changes, post more pictures of all the fish. A short (1 minute) video might show something too.

thank you! I will test those parameters later today and start doing this. Looking at the fish, I do notice the mucous. I thought maybe it was just the fish losing vibrancy due to the disease. Is there any medications you recommend? I did a salt dip two times yesterday in a separate tank for less than 10 min each and with 1 teaspoon rock salt per gallon water. I bought melafix a few weeks ago to help the other fish that died so I have that on hand as well but I wasn’t sure if I should try it again.

Colin_T · Dec 17, 2021

aposh said:
Is there any medications you recommend?

No medications at this stage. Just do water changes, gravel cleans and clean the glass and filter. Then see how they look in a few days.

aposh said:
I did a salt dip two times yesterday in a separate tank for less than 10 min each and with 1 teaspoon rock salt per gallon water.

Don't do salt baths. It is stressful to the fish when you chase and catch them. You can injure them if you lift them out of water when they are sick. They suffer stress going in and out of the salt and then fresh water.

If you want to use salt, just add it to the main tank. Use 1-2 heaped tablespoons of rock salt for every 20 litres (5 gallons). Keep the salt in there for 2-4 weeks.
However, don't add salt yet. Do the water changes and see how everyone is in a few days.

Slaphppy7 · Dec 17, 2021

aposh said:
thank you! I will test those parameters later today and start doing this. Looking at the fish, I do notice the mucous. I thought maybe it was just the fish losing vibrancy due to the disease. Is there any medications you recommend? I did a salt dip two times yesterday in a separate tank for less than 10 min each and with 1 teaspoon rock salt per gallon water. I bought melafix a few weeks ago to help the other fish that died so I have that on hand as well but I wasn’t sure if I should try it again.

What kind of test kit are you using? What kind of water conditioner?

How often do you perform water changes?

aposh · Dec 17, 2021

Slaphppy7 said:
What kind of test kit are you using? What kind of water conditioner?

How often do you perform water changes?

I use an api ammonia and pH test kit. pH is 7.6. I am heading to the store today to get one for nitrates/nitrites. I have always used water from my ground well for my tanks and have never used any kind of conditioner for it. I typically do 25-40 ish % water changes weekly. However, my parents have been taking care of the fish while I am at college, so they probably do it every week and a half to every two weeks.

Slaphppy7 · Dec 17, 2021

aposh said:
I use an api ammonia test kit. I am heading to the store today to get one for the pH and nitrates/nitrites today. I have always used water from my ground well for my tanks and have never used any kind of conditioner for it. I typically do 25-40 ish % water changes weekly. However, my parents have been taking care of the fish while I am at college, so they probably do it every week and a half to every two weeks.

Ever test the hardness of that groundwater? KH, GH?

A good water conditioner (Seachem Prime or API Tap Water conditioner) also renders heavy metals and other soluables in groundwater safe for fishkeeping.

aposh · Dec 17, 2021

Slaphppy7 said:
Ever test the hardness of that groundwater? KH, GH?

A good water conditioner (Seachem Prime or API Tap Water conditioner) also renders heavy metals and other soluables in groundwater safe for fishkeeping.

I will look for some conditioner today. We have had the ground water tested, but I don’t know the specific results. Nothing unsafe for people has ever showed up, but obviously fish are a lot different. We use a water softener.

Slaphppy7 · Dec 17, 2021

aposh said:
I will look for some conditioner today. We have had the ground water tested, but I don’t know the specific results. Nothing unsafe for people has ever showed up, but obviously fish are a lot different. We use a water softener.

Water softeners are often nothing more than salt...test your tap hardness, as well

Search

Search

Sick Corydoras

aposh

New Member

Attachments

Naughts

Fish Aficionado

aposh

New Member

Naughts

Fish Aficionado

aposh

New Member

itiwhetu

Naturally First

Colin_T

Fish Guru

aposh

New Member

Colin_T

Fish Guru

Slaphppy7

Mod-o-holic

aposh

New Member

Slaphppy7

Mod-o-holic

aposh

New Member

Slaphppy7

Mod-o-holic

Similar threads

Most reactions

Useful Links