We have well water, which is about as hard as you can get. I have been using Ecover tabs (I have never tried their loose powder, so not sure how well that would work) for a couple years now, and they are the best thing I've ever found!! They get the dishes very clean, don't leave spots on the dishes at all, and...best of all...don't leave any leftover detergent globs. They wash away clean. I've tried just about everything, and these are the best. I could never go back to anything else. The problem is, they can be hard to find. Whole Foods carries them, as do most "natural" markets. We just moved 7 hours away from our last house, and I was willing to buy 50 boxes every time we went back to visit family in case we couldn't find anyone that carried it around here. Luckily, we found a natural market that does.Â