So i got a new tank recently for the first time. I had 2feet long. Had 4 goldfish which died after having massive cotton wool fungus besides having full anti fungal drops. Idk how'd that happen. Then my brother gets 2 dollars which now ik needs a school which I'll get soon. So yesterday i saw the same thing with dollar fish on fins so I added same blue medicine to the tank. Today i could see some improvement in the fins but i noticed that there is some growth on their body as well and they aren't eating well. I gave them a bath in epsom salt to relax them and have them in a separate container with the same medicine. What should i do to save them. Super depressed!