Today’s thrifty living tip is use a pumice stone to clean hard water stains. This works really well with porcelain sinks, toilets, and even tubs. You can buy them at Lowes or any hardware store. We have an older toilet plus hard water. So deposits will build up over time, and it’s the original toilet to our 50 year old house. You do have to apply some elbow grease and it took out all the old stains. The inside looks brand new again. They are relatively cheap and I think I paid under $4 with tax. It’s a lot cheaper than most chemicals and it’s not toxic. I would recommend putting on a pair of latex gloves first.