ONLY sterbai corydoras infected

[Rocky998]

I've been dealing with horrible sterbai corydora fin rot and excess slime coat.
Yesterday one of them was REALLY not well and now today is shallow breathing and laying on its side.

Now, it MAY be an infection of some sort, but it's very weird cause it ONLY affects my sterbai corydoras, and even then it's not all of them that are showing symptoms. My larger corydoras are doing great. My peacock gudgeons are doing very well as well. Not a single scratch on them and this infection has been happening for months on end and I can't figure it out...

I really don't wanna nuke them with meds if it's not an infection. Because wouldn't all the fish have it if it was something like a parasite or bacteria? Basically I don't want the meds to kill them if the meds wouldn't even be doing anything.

I could try salt, although it is a lot of work...

I heard PH can cause these problems with fin rot, but from my research I've done, it sounds like it would have to be higher than my ph (8.1) to do any harm.
(By the way, if you're not familiar with my water conditions, I have HIGH ph, with LOW water hardness. I have a GH of 1-3. It's very weird, but it's the way the water here is strangely. I have not figured out how to lower the PH. If I could get a R/O system, I would, but I can't).

 

[GaryE]

Water change routine, and how long have you had the sterbai?

 

[CassCats]

Instead of salt, nuke the tank with very heavy tannins. Softwater fish respond better to tannins than with salt, and they're a better front line option before jumping to meds.

Clean water, then add tannins. Indian almond leaves are good, get the water a nice amber color.

 

[Rocky998]

Water change routine, and how long have you had the sterbai?

40-50% weekly (wasn't able to do it last week though)
I've had the sterbai since July of last year.

Instead of salt, nuke the tank with very heavy tannins. Softwater fish respond better to tannins than with salt, and they're a better front line option before jumping to meds.

Clean water, then add tannins. Indian almond leaves are good, get the water a nice amber color.

That would be a really good idea, but what if it makes the PH fluctuate? My KH is high, so I may not have to worry much but I do worry about there being a sudden drop creating a shock in the fish.

If I don't have to worry about that, I will definitely do that. How long should I keep it like that?

 

[GaryE]

Turn off the lights, get a flashlight, and have a good serious look along the spines of the sterbai. Do you see a velvety texture?

 

[Rocky998]

Turn off the lights, get a flashlight, and have a good serious look along the spines of the sterbai. Do you see a velvety texture?

So I just did that... I don't THINK I see that. I see, on some, the excess slime but no velvety texture on the spines

 

[Rocky998]

And on only ONE of the corydoras (NOT the one that's on the verge of dying), under some of the excess slime on its head, looks like his head is, not rotting, but like he got a big open gash. It doesn't look good. I just remember one day looking in and being in shock

 

[Rocky998]

And on only ONE of the corydoras (NOT the one that's on the verge of dying), under some of the excess slime on its head, looks like his head is, not rotting, but like he got a big open gash. It doesn't look good. I just remember one day looking in and being in shock

Also, I can try getting a photo, but I've tried before and it's so hard. All my corydoras are pretty skittish

 

[CassCats]

If you have a high KH, your pH won't dip much at all from the tannins

 

[Colin_T]

need pictures and videos or we're just guessing.

how long have they been sick?

did you add anything new to the tank in the 2 weeks before this started?

have you cleaned the filter in the last 2 weeks?

are you gravel cleaning the substrate when you do a water change?

 

[Rocky998]

need pictures and videos or we're just guessing.

That one that really wasn't well passed today. I got some photos.

how long have they been sick?

I think several months now. I tried increasing water changes for a while and it didn't help, but then I thought maybe the large water changes made it worse, so I made them smaller and it almost helped (maybe), but then it came right back so I'm at a loss.

I was gonna do salt a while back but we had a lot of stuff happening at the time where we'd be away and I couldn't monitor...

did you add anything new to the tank in the 2 weeks before this started?

I don't believe so. It just randomly started happening

have you cleaned the filter in the last 2 weeks?

No, but I did it in November sometime.

are you gravel cleaning the substrate when you do a water change?

I thought I was doing a fairly good job of it, but I hadn't done a deep clean of the sand in a LONG time, so today I did and deep cleaned the sand.
There was some stuff built up below.

I hadn't been deep cleaning the sand cause I thought I read somewhere that you shouldn't really do that with sand due to anaerobic pockets and gas releases.
But then I saw that some people do it every now and then.
Usually I only clean the very top layer

 

[Colin_T]

If you use a gravel cleaner to clean the sand, any anaerobic pockets of gas will go up the tube and out with the water.

Post pictures and video of the remaining fish.

If it only had excess mucous on its head and near the dorsal fin, it might have had a bad protozoan infection (maybe Costia). External protozoa like Costia, Chilodonella and Trichodina will cause a cream, white or grey patch/ patches on the head or body. If they are allowed to spread they can cause damage to the fins and gradually eat away the body before the fish dies.

The main reason for these types of external protozoan infections is a dirty tank or filter and lots of rotting organic matter in the tank High protein foods also contribute to it.

Two weeks of salt (2 heaped tablespoons per 20 litres/ 5 gallons) or Malachite Green will fix it. Be careful with Malachite Green, it can poison fish so check the directions for use on scaleless fish like catfish.

Before you add any medication, wipe the inside of the glass, do a huge water change, and clean the filter. Then increase aeration/ surface turbulence when treating.

 

[CassCats]

Sand you should only vacuum the top layer, but it's healthy to be able to stir every now and again with a chop stick to prevent anaerobic pockets or get trumpet snails who dig and stir it for you.


The fish posted looks severely deformed, very swollen in the shoulder area and a small head. Are they all shaped like this or is this the only one like that?

 

[Rocky998]

If you use a gravel cleaner to clean the sand, any anaerobic pockets of gas will go up the tube and out with the water.

Yes, I saw that only once when I did it yesterday lol. It was actually kinda cool.

Post pictures and video of the remaining fish.

I'll try later. It's hard cause they are all skittish.

If it only had excess mucous on its head and near the dorsal fin, it might have had a bad protozoan infection (maybe Costia). External protozoa like Costia, Chilodonella and Trichodina will cause a cream, white or grey patch/ patches on the head or body. If they are allowed to spread they can cause damage to the fins and gradually eat away the body before the fish dies.

This makes a lot of sense, BUT do you have any idea how this explains ONLY the corydoras being affected? My peacock gudgeons (even the males that usually stay in their caves near the substrate) don't have ANY signs of this infection at all

The main reason for these types of external protozoan infections is a dirty tank or filter and lots of rotting organic matter in the tank High protein foods also contribute to it.

This would kinda make sense to be honest.
There was a period of time I neglected my filters and I also was feeding them frozen brine shrimp with pellets that have a fair amount of protein (fluval bug bites and omega one pellets).

Two weeks of salt (2 heaped tablespoons per 20 litres/ 5 gallons) or Malachite Green will fix it. Be careful with Malachite Green, it can poison fish so check the directions for use on scaleless fish like catfish.

I'll start out with the salt and see how that goes then. Thank you so much!
Before I go right to salt though, do you think, like the other person in the thread said, that I could use Indian almond leaves?

Before you add any medication, wipe the inside of the glass, do a huge water change, and clean the filter. Then increase aeration/ surface turbulence when treating.

Will do!! Thank you so much!
I'll attempt to do that whenever I possibly can

 

[Rocky998]

Sand you should only vacuum the top layer, but it's healthy to be able to stir every now and again with a chop stick to prevent anaerobic pockets or get trumpet snails who dig and stir it for you.

I've thought about getting trumpet snails.
The sand needed a good turning. It hadn't been done for a while. So I'm glad I did it yesterday lol.

The fish posted looks severely deformed, very swollen in the shoulder area and a small head. Are they all shaped like this or is this the only one like that?

That was the worst one. My second worst has a gash in his head.
I literally named that first one (the one in the photos) stubby cause of his problems.

The rest aren't that bad. Only excess slime and fin rot. But even then there's some with no problems visible.
I have about 4-5 that look completely healthy