Whirling Dervish?
Hello! I have 8 goldfishes for about 3 plus years now. I started with them in a 10 gallon tank and they grew and are now in a 55gallon tank. One of them has passed through bruises, sick mouth etc. Now it started spinning rapidly. It cannot eat the feed from the top again. It mostly spin when trying to get feed from the top yet cannot really get it. Meaning it try to get it and misses. I really do not want it to die. How can I save it? I tried to change half of the water each week. Please help me. Thank you