Something is wrong

[Guyb93]

You have moments where you know something is wrong and I’m having one , for a while now after adding a few baby plecos I have noticed other fish scratching in the substrate and glancing off rocks , I added all my fry into the tank firstly in anticipation they would get culled by the other fish and too see if any of the weaker babies suddenly pass . Neither happened but within a hour they start to scratch like the others maybe once every couple hours I notice this so the problem must be within my main tank , no signs of ich or velvet so I’m leaning towards flukes , I was planing on emptying the whole tank and boiling off the sand and rocks then refill but I’m not sure if this would solve the problem or just cause me a few hours work , I know my filter would support the bioload so not worried about losing bb . But if anybody knows a “General Cure “ per say that would be great as I don’t want to treat a specific when I’m not 100% sure on what it is , currently no fish loss and my corys have no excess mucous or any signs of bad water quality, I keep my tank slightly warmer than I should around 28-29c so wouldn’t be an issue to raise beyond 30 if needed , I know something needs to happen just not sure on the enemy I’m fighting

 

[GaryE]

Wanting to do something and accomplishing something don't go hand in hand, and misuse of meds probably kills more fish the original problems.

You don't know what's wrong. let's start with the simplest problem, an ammonia spike from the arrival of a lot of fish? if you're heavily stocked (there's no info), that could be. If it is that, or a minor gill parasite, boiling the substrate and keeping that currently high heat would do harm. Oxygen's needed, and that suggests cooler water. You are several degrees higher than most Corydoras appreciate as is.

Someone will try to sell you a homeopathic type cure - they are accessible in North America and do nothing at all, so they are safe. But you don't want to spend $10 to feel like you're doing something, while doing nothing.

I would begin with a 40% water change - always my go to. Then watch and wait. Flashing against the substrate is common, and I have seen one or two week long flare ups that vanished on their own with clean water. In the meantime, you have time to go online and research fluke meds, just in case. What is available to you is different in every country.

 

[Guyb93]

Wanting to do something and accomplishing something don't go hand in hand, and misuse of meds probably kills more fish the original problems.

You don't know what's wrong. let's start with the simplest problem, an ammonia spike from the arrival of a lot of fish? if you're heavily stocked (there's no info), that could be. If it is that, or a minor gill parasite, boiling the substrate and keeping that currently high heat would do harm. Oxygen's needed, and that suggests cooler water. You are several degrees higher than most Corydoras appreciate as is.

Someone will try to sell you a homeopathic type cure - they are accessible in North America and do nothing at all, so they are safe. But you don't want to spend $10 to feel like you're doing something, while doing nothing.

I would begin with a 40% water change - always my go to. Then watch and wait. Flashing against the substrate is common, and I have seen one or two week long flare ups that vanished on their own with clean water. In the meantime, you have time to go online and research fluke meds, just in case. What is available to you is different in every country.

Water parameters are consistent and the tank is well established, the adding of fish was after a reduction in the bio load 5 full sized silver dollars were moved out of the tank along with a full sized Severum
I’m not really looking to treat the whole tank if a simple sterilising of the tank and substrate would work , most treatments iv saw contain formaldehyde and I’m not sure about using it as you say oxygen levels with the water being warmer and adding chemicals

 

[GaryE]

You could nuke the tank, but if the parasite is in the gills, all that work will be in vain. It isn't a substrate or water column issue.

Formalin is scary and might not even work for flukes. But I have eliminated velvet with mixes containing it with no long term effects I could see - the fish lived for years after, which is more than they would have with the parasite.

 

[Colin_T]

Any pictures and video of the fish?

If the fish have a disease, boiling the gravel won't treat the fish. You need to treat the tank and fish together.

Shine a torch (flashlight for the Americans) on the fish after lights out and see if they have a yellow or gold sheen on their body. If they do, then they have velvet. If you don't have a torch, photograph the fish with the camera flash on. It will show up velvet as a yellow/ gold sheen.

Velvet and white spot can be treated with heat (30C for a couple of weeks or at least 1 week after all spots have gone).

Most other external protozoan parasites can be treated with salt. Use 1-2 heaped tablespoons of rock salt for every 20 litres of water. Keep the salt in the tank for 2 weeks. Salt does not treat velvet or white spot but will treat things like Costia, Chilodonella & Trichodina.

 

[Guyb93]

Any pictures and video of the fish?

If the fish have a disease, boiling the gravel won't treat the fish. You need to treat the tank and fish together.

Shine a torch (flashlight for the Americans) on the fish after lights out and see if they have a yellow or gold sheen on their body. If they do, then they have velvet. If you don't have a torch, photograph the fish with the camera flash on. It will show up velvet as a yellow/ gold sheen.

Velvet and white spot can be treated with heat (30C for a couple of weeks or at least 1 week after all spots have gone).

Most other external protozoan parasites can be treated with salt. Use 1-2 heaped tablespoons of rock salt for every 20 litres of water. Keep the salt in the tank for 2 weeks. Salt does not treat velvet or white spot but will treat things like Costia, Chilodonella & Trichodina.

Im going to crank to 30c for a week or so and yeah I see the issues of fixing the tank but not the fish , il try the torch trick later on .
Photos I don’t have really there isn’t anything to really take photos of EBA had a white dot in his fin a few weeks past too large for ich and it was solitary I left it and it went I put it down to a calcium deposit but maybe in hindsight it was something more sinister, the scratches themselves across rocks don’t happen all that often and with keeping groups of most fish I couldn’t determine weather it’s the same fish scratching or another one in the group , I don’t feel like it’s an immediate threat to the tank but something just isn’t right

 

[Guyb93]

One of the fry have a single white dot on its tail fin though just noticed !can it be ich ? One dot on one fish out of a tank of 30+ fish

 

[Colin_T]

Quite often photographing fish with a flash will show up velvet before you can see the parasite under normal light.

 

[Colin_T]

One of the fry have a single white dot on its tail fin though just noticed !can it be ich ? One dot on one fish out of a tank of 30+ fish

How long has the fish had the white dot?
If the fish has had the white dot for a week or more, it is not white spot. The white spot parasite falls off the fish after 2-3 days at a temperature of 25C.

 

[Guyb93]

How long has the fish had the white dot?
If the fish has had the white dot for a week or more, it is not white spot. The white spot parasite falls off the fish after 2-3 days at a temperature of 25C.

I haven’t noticed the spot until now to be fair could be a day or a week but il keep an eye on it

 

[Guyb93]

Quite often photographing fish with a flash will show up velvet before you can see the parasite under normal light.

Fish under flash , I can possibly see the yellow tint you describe but not really sure how to recognise it

 

[Colin_T]

you need more of the light from the flash hitting the fish