https://www.thespruce.com/thmb/HAXdEi7om_Ply_73UTkbgk0m8K8=/4700x3270/filters:no_upscale():max_bytes(150000):strip_icc()/how-to-test-for-hard-water-1824904-01-3fdb383db2c14598820b144fca86cbc1.jpg