Any Salt would work Most folks Prefer Reef Crystal... IMO
I use Oceanic Salt but you use whatever you feel That works for you, on this Forum Salt mix is not a subject you don't want to start on. My suggestion is use it and stay with what works for you.... You can use as many different salt you like for a FOWLR
some start out using Instant Ocean and Other start out using Coral Reef pro. Pretty much Like i said your preference.... Hope that helps...