What can cause tile grout to soften? Surface of the grout(6 months old)is the consistency of whipped cream and brushing results in extremely cloudy water. A light scrape with a screwdriver ends up with a soft blob on the tip. It is not like the usual etching and erosion caused by acidic water (and water is in balance). It's as if the water has penetrated the grout (SGM Security Polymer Grout).