What are your parameters? What have you been feeding and what has it been eating? Those almost look like scrapes...are they fuzzy/cottony (if thats a word)? It does not look like Ich to me. I believe that poor water parameters and/or malnourishment can cause that sort of thing.
I've said it dozens of times, but my observations have been that saltwater fish being out into smaller that suggested tanks tend to have problems. Stressed fish pick stuff up a lot easier. When you read through all the "My fish has something" posts, it is rarely when it is is a proper sized tank. You also hear a lot of "but it is really small and I'm going to get a bigger tank later" stories. IMO
, the idea of buying it smaller does not make a difference. Most sites give a min tank requirement, which to me means you are starting with the min sized fish. The min for a Tomini is 75g and the min for a Koran is 250g.