Zep Mould and Mildew Stain Remover - Our ready-to-use, industrial-strength Mould & Mildew Stain Remover quickly removes any signs of mould or mildew. Zep Mould and Mildew Stain Remover - Our ready-to-use, industrial-strength Mould & Mildew Stain Remover quickly removes any signs of mould or mildew.