Macro with film is more tricky than macro with digital...
With film, you really need to use the 'right' film.
With the fine details you would expect with macro photography, you'll likely want a fairly fine grained film. You wouldn't want all those tiny details obscured by really chunky grain.
For film macro, the best very general advice I can give is lower is better as far as ISO goes. In general, lower ISO = finer grain. By low, I mean like 25 or 50.
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Also, if you use the 'right' film, the resolution is still higher than digital. It'll be B&W though - may or may not be an issue for you... Ultimately, the lens and your technique will be the limiting factors.