I sure don't want this blog to turn into "10 Easy Ways to Brighten Your Whites without Using Bleach" or anything, but I had to share this, its a case of my outsmarting myself.
When I was in college and doing the MBA thing, I took several marketing classes. One of the things we learned was about ways to increase the sales of your product by finding ways to get people to use more. "Lather, rinse, repeat" is one example. Arm and Hammer Baking soda is another (it seemed for a while there they had a new use for baking soda every week).
Anyway, I've been suspicious about the amounts recommended for various uses of household stuff for quite a while now.
About two months ago now, I noticed that the glasses in our dishwasher were coming out covered with a bit of a film. They just weren't sparkling clean. I re-wahed some, but it didn't do much. Then I thought that it was just a too-full washer, but over the next few days, the size of the load didn't matter. Then I refilled the rinse-aid dispenser. No good. Then I tried running the washer empty except for some stuff supposed to help clean the washer and get rid of calcium deposits. No help. I pre-washed the glasses. Zip. I was getting a bit frustrated. What's the point of a washer if you have to re-wash half the stuff?
Finally, I consulted the owner's manual and carefully read the directions on the back of the detergent box. they indicated amounts to be used based upon the hardness of the local water. Well, I had no clue what the local hardness in parts per million was, but I knew it certainly wasn't soft.
Based upon my marketing classes, I had been going a bit light on the dishwasher detergent. So this last time I filled it up about 2/3 of the way instead of 1/3 to 1/2.
The glasses were much cleaner. The next time, I loaded the detergent thing up the whole way. Super clean glasses. So now it was clear what was going on. I had been underfilling the soap dish, and thus the water wasn't getting enough of whatever chemical reaction was needed to keep the calcium from sticking to the glass. Busted!