- If the home has city water, call the city or town to get a report.
- If the home has a well, test the water using a kit or tests strips.
- Send a sample of the water to a lab.
- If the water is giving a foul smell and tastes bad but isn’t hard, purchase an inline filter that has a charcoal filter inside.
SOURCE:http://www.diynetwork.com/how-to/skills-and-know-how/plumbing/tips-on-determining-hard-water
