None of the fish in post 4 have Epistylis. The top group look like white spot, the bottom pics look like a smaller species of white spot. There's a number of species of white spot and they are all treated the same way (heat - 30C, Malachite Green, or copper).
Epistylis has stalks about 2-3mm long and little tufts on top. It looks a bit like fluff and can be treated with salt (1 to 2 heaped tablespoons per 20 litres of water).
Epistylis is not common in aquariums but is common in large outdoor ponds that aren't cleaned/ water changed regularly. They are commonly seen on shrimp and crustaceans farmed in dams.