After a bit of a struggle getting the pre-modecleaner out of its tank, we managed to examine the mirrors of the pre-modecleaner. Visually most looked okay, except one which showed some evidence of a film. It was not easy to see, nor photograph but certainly the impression is that something is there. This is most likely the reason of the pre-modecleaner's demise, which may have been the result of it having been stored with its tank lid on. Ed, Peter