my gold fish

Question
hi, i have a some goldfish that ive had for a few years now and i decided to buy some baby ones so i can watch those grow up too. well i noticed on one of my original older fish that his eyes had like white on it not cloudy but white growing right in the middle. which now over a 2 week period has  been starting to get cloudy.   once i put the new  3 baby goldfish in a day or two later they had some white stiff growing on them. so i bought some fungus treatment and have been in treatment for 2 days now. it doesnt seem to go away it seem to have now once i treated to have eaten away a part of the fishies tail with the white on it as well. i dont know if they have a fungus or tail rot or is it the same? what about my big older one whats going on with him.  i vacuumed the tank clean the filters, well now i have the filters carts out  for treatment. im very concerned. what to do?

Answer
Hi There,

Fungus can usually result in tail rot in severe cases.
Check your water quality as these are both caused by poor water conditions.
For the fungus which is causing the tail rot, add some methylene blue which is available at your local fish shop.
I also recommend using a cotton bud and using some of the mehtylene blue apply it to the affected area of the tail wound. This will help heal the wound.

Hope this helps,
Chloe :)