I have the same problem w/ permanent water spots. I don't know what causes it. We use All Free & Clear detergent and our washer is a Fisher & Paykel that has a tube you pour it into. Although the tube has holes in it, not much gets on the clothing. Even then, I always turn the water on immediatly.
I don't know how to prevent the water spots happening in the first place. But I do know how to get the water spots out of your clothing now. Trust me, this really works. It is
Shout ® Advancecd Gel Before we bought our washer & dryer, we were doing our laundry at the laundromat. Most of my shirts got ruined because of this. I got dark water spots and other unidentifiable stains on them from the stupid laundromat. I had to buy a bunch of new shirts to replace the ones I had. And alot of those weren't that old either, But I bought the new ones and held on to the old ones. "Just in case" I thought.
Well, I saw the commercial for the Shout® stuff and how it could get out tought set in stains. So I bought a bottle. A little spendy for the size but found out that it is worth it's weight in GOLD!
The Shout® Advaced Gel took all of my stains out. A few of my really bad ones had to be done twice but they all came out! Stians that had been in there for more than 6 months! My fiance had a t-shirt given to him that was from a thrift store. It was white w/ a Final Fantasy logo on the front of it. The white was very digny and had some very dark brown stains in some spots like someone had spilled coffee or soda on it. The Shout® Took them all out! It was like getting a whole new wardrobe!
All I did was spray the soiled spots and let it sit for 1 week (7 days) and threw them in the wash. When the wash was done, I checked them. On those where the stians came out, I t hrew in the dryer. Those that still had stains, I re Shouted w/o putting in the dryer. I let them sit for 3 days and then I rewashed & dryed.
I was so amazed! A product that had a commercial that was 100% true! I can't believe it. I highly recommend the Shout® Advanced Gel.