Montblanc offers both water-soluble inks and iron-gall inks such as the royal blue (component damage is, according to the maker, not to be expected, only more frequent cleaning is required); water-soluble inks can be removed with clear water, document-proof inks need more elaborate methods. With regular use, flushing with clear water before each refill (typically every three weeks) and an overnight stand in a glass of water suffice; the nib cannot bend in the process. Iron-gall residues dissolve with the cleaning agent of a silver-cleaning cloth or in an ultrasonic bath. Hard tap water, in experience, leaves slight limescale deposits and cleans worse than soft water, which is why in lime-rich regions the use of distilled or filtered water for the final rinse is recommended.