Zinc sulfate is offered as mono-and heptahydrate. Which hydrate is recommended for internal use?

A hexahydrate is also mentioned In the European Pharmacopoeia. The USP only mentions the monohydrate, which occurs as a powder while the other two are crystalline. In the overflowing of the monograph ë N in the European Pharmacopoeia, I noted that both Hexa and heptahydrate are known as "fluency". Thus, the monohydrate is best suited for powder mixtures, both for oral administration and external use. This is confirmed by the fact that Nutri ë Nten with zinc sulfate, which are found on the Internet, contain the monohydrate.