I have a container pond that has two platys and two feeder fish. Yesterday, I found out that one of the platys had missing scales and the places where the scales were missing had fluffy stuff hanging on its body. Its tail was also nipped a little bit. Then, today, I found out my other platy had the exact same thing too. And a week before, one of the goldfish had the same thing and died a few days later. What can I do? I don't want it to die. Thanks for any help!