Sick Fish, Please help..

[Raych]

Hi, I hope no one minds me posting, I have a 35L cold frshwater tank with one fantail goldfish. He has been fine for a long time, but since last week one of his gills looks really sore, almost as it it is bent back on itself, and is very red. I have done a water test and everything is ok apart from my nitrate level which is sky high. I have done a 30% water change every day for the last week but this hasnt made any difference. There are live plants in the tank, and we can think of no obvious reasons for these nitrate levels. Is there anything I can do to lower these levels or to help squeak? (My fish)

Again, sorry for posting, I know this is a tropical site, but hoping someone will be able to give me some advice. Thanks.

[William]

Keepers of all kinds of fish are more than welcome so don't worry ;-)

The nitrite is more than likely the reason behind your problems. If the water changes doesn't make any good I have to ask two question, is there much debris, a dead fish or something like that present in the aquarium?

How much do you feed?