Hello

For someone to answer that they will probably need your tank size, filter etc. If its quite a small tank it might be best to do a good water change to take out some of the bad bacteria as the tank is not mature. Probably have to do a frequent water change like 15-25% and go easy on feeding just stop the bad bacteria spiking. I think im right in what im saying someone else will give you better advice. There is also some good advice already on the forum you can find it here http

/www.fishforums.net/index.php?/topic/277264-beginners-resource-center/
Hope it helps!