Hi there. I have a 60g with a aquaclear 110 and 7 fancy goldfish (too many I know that now) that has been up for almost 3 months now. 6 of the fish are 1-2" and the 7th is a 1" baby. The fish seem happy enough but when I finally bought a test kit a few days ago I found out that my ammonia levels were high (4.0 range). The nitrate and nitrite were both not registering and the ph is around 7. The odd thing is that when I tested my tap water for ammonia it was in the 1.0-2.0 range before it even went in the tank. I treat the water with safeguard+ dechlorinator or whatever its called before I add it. About a month ago one of my fish had fin rot so I made the mistake of adding tetracycline to the tank. Im sure that wiped out everything in there. Ive done many many water changes since then and rinsed the filter sponge in old tank water many times as well. I have also replaced the carbon bag but the ceramic or clay bio pellet things are the same that have always been in there. What am I doing wrong? I assume if my tank was cycling at all I would see a rise in nitrate and nitrites but im not. I do weekly water changes of about 1/3 and I dont know what else to do. Any advice would be appreciated.