I'm at a loss as to how to clean shower grout. Thankfully we don't have any problem with mildew, but it's next to impossible to clean the discolouration that builds up after about a week without scrubbing so hard that it wears away at the grout itself. Is there a product or a device that does the job? Hotel showers always look so fantastic, I'm convinced there must be something out there that works. Thanks in advance for all advice :)