Many people have a hard time telling the difference between ich & velvet, or incorrectly assume all "white spots" are ich. Below are some pics of a Hippo Tang - the first one has ich, the next 4 show velvet. Ich (Cryptocaryon irritans) - Oval shaped white dots, can usually be counted. These remain on the fish for 3-7 days before dropping off to continue their lifecycle. Velvet (Amyloodinium ocellatum) - Smaller round white dots. Oftentimes completely covering the fish & too numerous to be counted. These remain 12 hrs - 4 days before dropping off. Velvet is a far deadlier, more dangerous pathogen than ich.