jlk
Aquarium Advice Addict
Good luck! What I would suggest you do now is to remove the carbon filter & toss it. Replace it with another type of nonchemical media such as filter foam, filter floss, bioballs, etc. Then start feeding your tank with an ammonia source (bottled amm, fish food, raw shrimp, etc). The med wont affect your good bacteria. After you are done treatment, do a big water change & remove the media to a container of conditioned water & run new carbon for a day to remove the med. Then replace with the old media. Continue to dose ammonia through out the process so your tank stays cycled. Also, take the time now to research fish you may be interested in stocking. I would skip another goldfish unless you plan on upgrading your tank in the next few months or less.