Help Sick Comet Goldfish, Fin And Body Rot? Help Diagnosing The Cause.


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4 years
Hey Guys,
I still have this sick comet goldfish, he's been sick for probably 4-6 months at least and I can't for the life of me figure out why.

He lost a few scales on his stomach, which looked like it got further infected. That area has been going through cycles where it looks like it's healing or it's white and fleshy but smooth, and other times it'll be red and obviously inflamed/raw/rough and fleshy.

He's lost one of his pectoral fins to rot, it became slightly fuzzy (couldn't tell if it was fungal or bacterial). Now it's just a small stub. He's got an appetite still. I was feeding him omega goldfish pellets lg size, my co-worker mentioned that it could be due to his diet, and told me to start feeding him higher protien items (something with his gut and an internal bacterial infection), so I'd add a few hikarI carnivore pellets with his goldfish pellets. They get maybe 3-4 large pellets a day (+ the few carnI pellets).

He's active though he can be a bit listless. Hanging out at the top and resting more than usual (at the top) while my other one swims in the middle column more. He's never on the bottom though, and doesn't appear to have issues in buoyancy or direction.

I do weekly ~50% water changes on my tanks. The tank consistently tests at close to 0 ammonia, 0 nitrite, and 20-40ppm nitrate. Its about 2-3 years old (the tank).

I do have loaches, and some cichlids in the tank with him (this is my 'catch all' tank...currently working to sort it out). I've noticed they will bother this goldfish from time to time, could it all be caused by them picking at him (has the infection gone and it's just been irritated)?

If you're wondering why I haven't QT'd him yet, I don't have a tank large enough and I don't want to see him die in a cramped 10G. BUT, he's stuck it out for this long with an obvious will to live. I do have a 20L with just 2 convicts that I'm looking to donate, I want to start quarantining him in there, but I don't know what meds to start with. Anyone have any idea's as to what may be the cause of this? I've got another goldie in there, same age, that's never been affected.

Caption To the Pictures: The redness is the area that's inflamed right now, but the problem area receeds all the way down his middle stomach. He has a large area that's void of scales, it's white and fleshy, and continues up to the red area.

In one picture, you can see both the lost pectoral fin, and the red/inflamed area. It's all only on one side. He flips around and you'd believe he was a healthy comet.



Well Known
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Houston, TX
2 years
separate him (you can use a large storage container if the 10 gallon tank is too small) then use a wombo combo of Kanaplex and Metroplex.

I don't think it has to do with diet. I feed mine the small sinking Omega One in the morning and the Kelp Veggie pellets in the evening.

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