That looks like the beginnings of head and lateral line erosion to me. Doe it look like a hole forming in the fish? It's a fairly common disorder in large angelfish and tangs, but I don't recall ever having seen it on a tomini before. I don't think they know for sure what causes it, but I think diet is the main suspect. If that is what it is, the good news is it isn't immediately fatal. The bad news is the fish gets pretty ugly over time.
Ich looks like salt grains on the fish by comparison.
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