There is salt made specifically for fish dishes. I've used it a few times in the past, but while there is nothing wrong with the taste of the "flake salt", it is a very disturbing feeling to be eating fish meat and constantly feel these "crunches" from the salt flakes... or are they bones?
This leads me into my personal, very seriously meant theory: the salt is shaped like that specifically to conceal possible existing fish bones in the fish, so that the eater can't tell the difference and, supposedly, enjoy the meal without worrying about the bones.
Those small, thin bones are the reason why I stopped eating fish. Every time I took a bite, I couldn't enjoy it at all because I feared, and continuously encountered, such instances. The worst part is that I actually like the taste of the fish dishes, but can no longer eat it because they apparently still don't have the technology to verify that there are 0% bones left in the piece of meat that they sell to consumers. I would happily pay a premium price to get a "verified bone-free" fish to eat. Maybe some sort of scanning would be feasible?