Quote Originally Posted by Tom1956 View Post
I wouldn't see how any filter would work. Filters filter particulates. The chemistry is in solution. Besides, the standard developers and fixers are for the large part biodegradeable. And stop bath is about the same as vinegar. I have a septic tank too. I wouldn't worry, unless you're going into production or commercial.
Typically selective means that not (only) work mechanically but chemically as ion-exchangers and activated carbon are called filters too.