I've been keeping fish on and off for several years but I've never seen this one before. This has seemingly come from no where. I do not know my water quality numbers but I had a sample tested at the local store and the guy said it was just fine. I've go a 36gal, temp is ~75deg and plenty of filtration. All my Neons have this and my Platys are starting to show signs. They all act normal and eat just fine. Any ideas? Thanks in advance.