Naphthalene sulfonic acid/formaldehyde condensates (i) may be used in a composition for cleaning hard surfaces to reduce the rain effect and/or the film effect, (ii) may be present in a cleaning composition for hard surfaces in combination with one or more other anionic and/or nonionic surfactants and (iii) may be used in a process for reducing the rain effect and/or the film effect on a hard surface treated with a liquid cleaning composition, the surface being treated with a liquid cleaning composition in concentrated or diluted form containing one or more naphthalene sulfonic acid/formaldehyde condensates.