How do I remove calcium scale from different surfaces?

For light scale on tile, use a 50/50 white vinegar and water spray — let it sit five minutes, scrub with a soft brush, rinse. For stubborn buildup on glazed tile or porcelain, wet a pumice stone and gently grind it off. Avoid vinegar and pumice on unglazed surfaces like natural stone or plaster — use a non-acid calcium remover or a stiff nylon brush instead. Don’t use steel wool or bleach; bleach only whitens, it doesn’t dissolve calcium.