API = crap.
Given that it's a best guess on the ailment, I'd recommend Hikari Ich-X - saltwater version.
It contains Formalin which is effective against many different kinds of protozoan as well as Ich.
It's been some days since you first posted - sorry I'm late to the game.
It could also be Brooklynella and Ich-X can treat that too.
Treat in a quarantine tank ONLY not the main display. That product may say it's reef safe but I wouldn't bet on it.
Jenn
