thats the treatment i used for my ich issue

i also was overkill on my water changes.
not sure your schedule, but i'd up the changes to keep the water super clean/healthy.

additionally-not sure how this will work w/ the sand, but part of the ich cycle is the eggs in the i'd do your best to keep the sand clean/clear of those. b/c once you see the "salted" look off, is when the ich is in another stage of its life cycle. so thats why we continue to treat like 4 days to a week longer to make sure all variant of the disease are dead.