Is it possible to restore the original whiteness of our kitchen cupboard doors? I think my doors are plastic. For melamine doors, a melamine primer should be used before repainting. Beware, “high gloss” units have a thin film of plastic, which can get scratched and peel. In this case, your best option would be to replace the doors. For natural wood you could try a product called Woca Softwood Lye, which can be used to maintain the original “whiteness” of wood. A 2.5-litre tub costs around £23.95 with a coverage of about 10m sq per litre. This is mixed and applied to thoroughly cleaned and sanded bare wood. It should be allowed to dry completely, after which the wood is polished. Then the wood is cleaned with a natural soap or oiled. If your kitchen doors were previously painted, then you need to thoroughly clean and rub them down before repainting them. If you strip the paint down to the bare wood you will need to use a primer before repainting. I have noticed tiny millet-size black bits that float around in the bath water. From my investigations, they only come from the hot tap. They don’t appear in any other sanitary ware either. What is causing them? It sounds as if they are...