I have  a pretty basic question....how should working solutions of special stains (not Hematoxylin or Eosin) be stored for re-use?  In particular, I'm wondering about Fast Green, Acid Fuchsin/Ponceu, Orange G.  I've checked my books, but I can't find whether they should be shelved in brown bottles or not.  Is it important?  I've routinely stored special stains in brown bottles, away from light, but what's the official reference for this???  Are the really light sensitive or is that just my "habit"?

Thanks-
Mary