Hi Mike,
Re. your question about replenished Microphen, here is a long thread in which Ian G. describes it's characteristics and replenishing techniques very thoroughly.
http://www.film-and-darkroom-user.or...microphen+fans
He is a wealth of knowledge on the subject. Well worth a read through the entire thread.
BTW, according the Ian, Microphen is near enough to ID-68 as to be more or less interchangeable, and he provides a link to the formula for the latter on his web page.