Just for future reference, that looked too large to be ich. Still, it is a good idea to observe your fish closely every day. Ich does fall off and then multiply and return to different locations on the fish, in increasing numbers each time.Update spot fell off it was a fleck of debris haha
I don’t have one unfortunately I might be able to setup one in the next couple days but I’ve never set one up beforeSome of those smaller spots could be ich. The big spot at the top isn’t ich though. What is your ability to move the fish to a hospital tank for treatment ?