My Goldfish Shelly has something wrong, but I don't know what.

[OpheliaLenore]

My goldfish Shelly had ich, which I treated with antibiotics (my friend who owned a fish and reptile rescue told me to use antibiotics). After a week on antibiotics, Shelly got a little red mark near her tail. After a couple days, she developed what looks like a pimple on the red mark. The pustule has gotten much bigger, and more lumpy. I included two photos, but they're not good.

I hope someone can tell me what this is and how to treat it.

EDIT: This tank is the QUARANTINE tank. I rarely EVER keep a fish in something like this. Please don't come after me for how it looks

 

[Autumnsky]

Not sure what this is, I am terrible with the pics, but when a fin is bent back / cracked it can look like that.

Does it seem that spot of the tail is misaligned at all.

 

[OpheliaLenore]

Not sure what this is, I am terrible with the pics, but when a fin is bent back / cracked it can look like that.

Does it seem that spot of the tail is misaligned at all.

She seems fine other than the white pustule/pimple with a red ring around it. That's the weird thing. She behaves very much like her tankmate Eric, except lonelier because of quarantine.

Like I said though, as soon as I got her, she had ich. So I don't think I've ever seen her in a healthy state. I got her and Eric together, but she seems to be the only one sick.

 

[Autumnsky]

What are the water parameters?

How long has the tank been set up?

 

[OpheliaLenore]

What are the water parameters?

How long has the tank been set up?

In the tank she was in before quarantine, it had just finished cycling. And it's currently
Gh: 75 ppm
NO2: 0 ppm
NO3: 10 ppm
Cl2: 0ppm
KH: 40 ppm
pH: ​7.2


The quarantine tank is


GH: 75 PPM
NO2: 0.5 ppm
NO3: 25ppm
Cl2: 0ppm
KH: 80ppm
pH: 7.2

 

[Autumnsky]

Missed seeing the ammonia reading.

In Eric's tank you missed the number for NO2 /NitrIte.

NO2 - .5 is too much in the QT tank Do some water changes to get that number to 0 if at all humanly possible.

You might check the tap water using so you aren't changing water with tap water with elevated numbers. (That is a frustrating thing to not realize your tap water already has ammonia or Nitrite in it.)

You can use Prime water conditioner or another name brand water conditioner which treats / neutralizes the chlorine/Chloramine (if your water department ever uses it) heavy metals, and detoxifies ammonia, nitrIte and nitrate. I haven't used it but I know Fritz has one called Complete.

https://www.seachem.com/prime.php

https://fritzaquatics.com/products/fritz-complete

 

[OpheliaLenore]

Missed seeing the ammonia reading.

In Eric's tank you missed the number for NO2 /NitrIte.

NO2 - .5 is too much in the QT tank Do some water changes to get that number to 0 if at all humanly possible.

You might check the tap water using so you aren't changing water with tap water with elevated numbers. (That is a frustrating thing to not realize your tap water already has ammonia or Nitrite in it.)

You can use Prime water conditioner or another name brand water conditioner which treats / neutralizes the chlorine/Chloramine (if your water department ever uses it) heavy metals, and detoxifies ammonia, nitrIte and nitrate. I haven't used it but I know Fritz has one called Complete.

https://www.seachem.com/prime.php

https://fritzaquatics.com/products/fritz-complete

Okay but she had these issues before I put her in QT so I need to know what's wrong with her. The water levels are not the issue because Eric is fine and was fine the whole time they were together. I need to know what's going on, and how to fix that.

 

[Autumnsky]

Without proper water parameters for her to not be stressed in further, she could become ill from poor water quality. So in the interim figuring it out she should have the best water quality possible.

Short answer is I do not know what is wrong specifically. But there are a series of things to look for and check.

All will be made worse if she is stressed by her water conditions. So I am trying to help you.

Here is a link below for a bunch of illness issues. The reason I initially was wondering about the water conditions is that there are conditions from ammonia poisoning and nitrate poisoning which can begin as splotches of red on the fish. Nitrite poisoning causes red /pink gills to turn a brownish to grey color.

Fish lice and external parasites can cause spots which could look like a pustule. But you recently treated for Ich.

A broken fin can look similar.

A bacterial infection might make it look like a pimple, infection but so could a virus.

So until a member who has experienced this or a fish lab tech or doc or an assistant pops in, you can go through the possible injuries, and illnesses to try and identify it.

The main ones I touched upon.

She is already under some stress due to the recent Ich and treatment which will stress a fish.

NitrIte poisoning can damage the internal organs and cause a death weeks later.

So all of it is important and I do understand of an urgent nature. I just can't really help any more than that because I can not immediately ID what it is.
https://www.aquariumadvice.com/fish-disease-index-for-diagnosis-and-treatment/
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