A:Answer Regrettably, there is no way to gauge how this LG 24" Top Control Dishwasher with QuadWash™ and EasyRack™ Plus, Model # LDP6797ST will hold up to hard water over time. Geographically, more than 60% of the USA suffers from hard or very hard water with an overwhelming 85 percent of the USA having hard water. Hard water can be potentially corrosive and damaging to domestic appliances, pipework and central heating boilers. The six metro areas that are notorious for having the hardest water in the country are Indianapolis, Las Vegas, Minneapolis, Phoenix, San Antonio and Tampa. If you have issues with hard water damage to your appliances, you may want to look into a Single-tank cabinet or Twin-Tank (Dual-Tank) water softener. An Eddy descaler is often an effective protection against the problematic effects of hard water...^IFV