Brown Scales And Septicemia???


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Why are my fish developing brown scales and fins? -Not ammonia poisoning.

Background: So we had 2 carnival goldfish for 10 years (6”) and 1 of them died in April. The other goldfish’s personality completely changed, was hiding all the time, was skittish anytime I came around, never came up to the corner begging for food, etc. I figured he was sad/depressed that his buddy was gone. So I waited a few weeks to see if it died too but it didn’t so we bought a new 2” comet goldfish on April 20th. The old goldfish started to perk up and he seemed to be getting happy again. But then this new goldfish started picking on the older bigger one, constantly bumping it, pecking at it, swimming under it, following it around all the time, basically bullying it. I bought a floating breeder box to separate them. I let the little one out to swim a few hours a day and then put him back in the box (time out) as soon as it started being a bully again.

During that time, the older one started getting happy again, started acting normal again. But then a few days later, the older one started to get red blotches on his body, red streaks in his fins, lost appetite, stayed on the gravel in the corner, clamped fins. So I read for hours trying to find out what was wrong this time and I came to the conclusion it was septicemia. That started on May 13th.

So to treat this I started by adding the recommended amount of aquarium salt to reduce stress. The next day, I added Melafix and Pimafix. The third day, he was perking up again and started to eat. I also read that he might be constipated so I fed a few shelled and cut in small pieces of peas. He kept getting better and better and he was completely back to normal in a few days. He also pooped a clear see through poop. And a few days later, he pooped a light salmon colored poop. (Those are the only 2 poops I have ever seen it have over the past 10 years.)

In the meantime, I moved the new goldfish, (which now has the name, Little Demon, for being a bully,) to a new 65 gallon tank that I set up the week before. I was feeling guilty that he wasn’t able to swim freely. Being that it was still cycling (using fish flakes), I would remove him if there was a huge ammonia or nitrite spike back to his floating box which is now the hospital tank.

During this whole time, I monitored the water every single day and both tanks had and currently have good parameters. I also have been doing small water changes in the old tank and replenishing the correct amount of aquarium salt and continuing treatment with Metafix and Pimafix.

Old tank - always 0 ammonia, 0 nitrites, 10-20 nitrates, about 7.4 PH. 68.5 - 69.3 degrees

New tank - 0 ammonia with only 1 day at .25, no more than .25 nitrites, between 10-40 nitrates depending on the day. about 7.4 PH.

>>>> So now here’s my newest problem. These 2 fish have been in separate tanks for over a week and they both started to develop brown spots on their scales and fins 2 days ago. It is worse on the small comet in the 65 gallon tank. The older one also has a brown dot over his left gill and today a new brown dot near his tail. And it looks like holes are getting bigger on both sides of his head. (Where ears would be above the gills) They both are acting completely normal swimming around happy as can be, still eating great, still in separate tanks.

I haven’t been able to find out what this could be. All the explanations seem to suggest ammonia burn but the old tank never had any ammonia and the new tank had only a small amount (.25) on one day. So I do not think it could be ammonia burn.

What could be happening? Did the new comet bring all these diseases with him from his breeder? I’m so tired of stressing over these fish for the past two months.


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More than 10 years
Theres a good chance youve introduced something to your tank since you didnt qt your new fish. I would treat them for parasites as a general precaution until you figure out whats exactly wrong
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