I have inherited a Miele G540 dishwasher, which is almost as old as me. Was my Grans and was hardly used – and as it has just had a new pump, it is a shame to dump it. Anyway, it seems to work fine but I need clarification of how to put salt into it as there are no instructions. I presume the salt reservoir is the large circular plastic cap in the base of the cabinet. However, when the cap is unscrewed, there are only 2 small holes inside – surely this is too small for salt to fall through. Also, there is a setting called “reactivate softener” How does this work???