Conrad Weiser [1696-1760], who came later to America from Germany, first lived with his parents in New York.  In the 1730's he moved to Philadelphia, where he came into contact with the remaining followers of Kelpius.  He had been known as Indian Missionary and lexicographer, and in later years was a judge and a politician.  He also was a friend of the second leader of Ephrata, Peter Miller, and later became a prominent member of the Ephrata Cloister.

Those who, like Kelpius, were true mystics were a minority, even if everyone who followed him to the New World had attained to a certain understnding and direct experience of Rosicrucian principles and Universal¹ spiritual laws.  As Rosicrucians, they continued to participate in personal religious practice and public pursuits that was a natural part of life in America.  Therefore, there is no record of just exactly what activities by the Kelpius group were designated as Rosicrucian in the modern sense of the word. 
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¹Refers to immutable laws that operate universally throughtout all of life on Earth, without regard to personal prejudices or erroneous opinion.