Goldfish sore?

[Scargirl]

I have a 10 gallon tank and 7 goldfish. I have had them for about 3 years and I have no idea what age they were when we got them. They are all pretty big. The littlest goldfish (It's white) has like a sore on it's back by the fin. I don't know if it is a disease or what and if it is a disease I don't want the others to catch it. Any idea what it is?

[BrainGirl]

In a tank that size, all of your goldfish will be stunted by now and suffering from stress among other things. Goldfish are high bioload fish so I'm guessing your ammonia, nitrites, and/or nitrates are sky high. What kind of a filter do you have on there and what is its rating? Do you have a test kit? What kind of goldfish are they? If commons/comets they would need several hundred gallons to grow properly. If fancies, that number of fish would probably need at least 150 gallons at a rough guess.

[Scargirl]

Can any of that lead to sores?

[Vicki S]

Heya scargirl have you any pictures of his sores?
I have a 7yr old boy he recently had a big red blotch on his belly n now three months on he's fine the can be stunted due to tank size but wat is your tank in litres as I always think gallons sound small

[Piebald]

10 gallons is about 38 litres

[Vicki S]

Originally Posted by Piebald

10 gallons is about 38 litres

Thank u I'm hopeless at gallons

[BrainGirl]

Originally Posted by Scargirl

Can any of that lead to sores?

It can lead to all kinds of diseases but ultimately it's going to lead to death. I'm sorry to tell you this but goldfish can live to 20 or 30 years of age when kept in good conditions. They might live 1/4 that at most if they've been stunted.

Have a read of this: Stunted growth means stunted lives — Seriously Fish

[Vicki S]

Originally Posted by BrainGirl

It can lead to all kinds of diseases but ultimately it's going to lead to death. I'm sorry to tell you this but goldfish can live to 20 or 30 years of age when kept in good conditions. They might live 1/4 that at most if they've been stunted.

Have a read of this: Stunted growth means stunted lives — Seriously Fish

But if the fish are treated for this and maybe if scargirl upgraded or rehomed or found a pet store that would take them surely they would be fine?

[BrainGirl]

They've been in there 3 years, they're already stunted. They'll probably be happier, and it will certainly be easier to keep the tank water clean if they're moved, but they won't "outgrow" stunting. The best option for them is to be given a pond to live in. If they're commons they would have had the potential to reach 2 feet in length. In such a small tank she's going to need to do daily water changes along with running an extra-large filter to keep on top of their waste output.

[Scargirl]

Originally Posted by Vicki S

Heya scargirl have you any pictures of his sores?
I have a 7yr old boy he recently had a big red blotch on his belly n now three months on he's fine the can be stunted due to tank size but wat is your tank in litres as I always think gallons sound small

What do you mean? To big or too small? I thought goldfish can only grow to the size which fits the tank they live in?