My childrens' goldfish is lying on its side on the bottom of the tank, in a arched position with its' head down & tail down. It looks almost dead, but it is still breathing & occasionally moving slightly, but staying in the same position.
Yesterday the fish curled up in the 'pot' (bought form a pet shop) that is in the tank but we took it out as this is where a fish went to die about a year ago. After this he seemed okay for a while, but islooking very ill today.

There is another fish in the tank but he seems fine.
I was going to clean out the tank - but I'm not sure what to do for the best.
The fish is two years old.

They are fed on King British goldfish flake food, and about a month ago we starting giving them floating food sticks as well.

Is there anything I can do? What is likely to happen.
PLease help.

Thanks

Karrie your fish is seriously ill and I feel only a miracle could save it at this point.

Sometimes fish deteriorate quickly like this and the cause is a mystery, especially if it was not showing any odd symptoms beforehand. I would guess that your fish either has some type of organ failure or it has a serious internal bacterial infection.

There aren't any antibiotic type treatments available in the UK other than tetracycline hydrochloride or triple sulfa. I would suggest trying triple sulfa if you wanted to try anything but really I think it's too late. Very sorry.

I agree with Annette, once a fish starts to arch then theres not much hope im afraid.
Can you fill in as much of the red box above as you can please. Staff at pet shops can usually test the water for you if you take a half a cupfull in.

How is the fish doing?

ohh, this sounz very bad, i lost 5 fish this way. I did almost evrything i could do, then had to dispose of them because it took allot of time, and everything didnt seem to work. At the end, i found ammonia to be the problem, then i got it down to 0. 5 monthz later, same problem, fish wasting away. This time it was nitrate and nitrite. So now all fish look fine, and i didnt have any new deaths. But my tank was overstocked, and biolagical filter isnt good because im using Phos-X and ammonia remover cartidge. If i remove these then they will go sky high again. Hope u find the problem. Best Wishez.