hey bazilianguy im currently dealing with this particular issue. Bifidobacterium is obviously depleted if we been using antifungal remedies because antifungal remedies kill Bifido.
Now The colon holds the most bacteria in the body, way more than the small intestine so it would make since to repopulate the bifido. the problem is bifido and laco bacteria cant colonize without a clean intestine. so i been using vsl3 to clear the path in my intestine followed up by some colonizing kefir.
i use nystatin enemas only to keep candida down while i repopulate because as of late nystatin caused my Clostridia to rise because candida competes with it.