Hello, today I found one of my new comet goldfish outside of the tank. He seems ok and is active. But his top fin is gone, and his once long back fin is smaller. He is having a little trouble swimming. Is he going to be ok? I've had the fish for 1 night, in a 30 gallon tank. The water has been tested and it is good, and there is a pretty nice filter in there. I spot clean the tank every so often, and pick up all the leftover food. I have 3 other goldfish in the tank, 2 smaller comets, and 1 small oranda. The comets are new so they are still adjusting, but the oranda has been in there for over a week. I put a before and after photo.