I added a couple new corys to my 46 gallon tank last Friday (ammonia 0, nitrites 0, nitrates 5) and unfortunately did not quarantine them. One of them now has fungus on her two pectoral fins (white, fuzzy). I removed her to a quarantine tank that I set up using water from the existing tank and a handful of gravel from it as well (so she had something to dig around in). I added API fungus med, which was the only one we could find. This was on Sunday (the fungus showed up Saturday). She is going dowhill rapidly. I know the tank is stressing her, as well as being alone. She was doing great, very happy and active in the regular tank. Only issue was the fungus. What should I do at this point? I don't want to lose her. I am supposed to add the second and final dose of meds to the water tonight. Any advice would be greatly appreciated. She is miserable right now.