I performed my own personal experiment this afternoon...there are three pool stores within a mile of my house, all on the same road. So, I brought a water sample to all three. Here are their different results, from their computer printouts:
Store 3 (didn't have CYA reagents to test with):
They all want me to add Calcium Chloride to increase hardness (I have a vinyl pool, but have a heater...is this a reason to increase hardness?) Stores 2 and 3 also want me to add more of what we all know is Baking Soda; Store 3 also wants me to raise pH.
I had brought a sample to Store 2 on Saturday, and their results then were:
Saturday afternoon I added 12 lbs of baking soda to start boosting alkalinity. I also turned my inline chlorinator on yesterday afternoon after we had a bunch of people in the pool, but other than that, I haven't added anything else. I don't know whose numbers to believe. Maybe none, and I'll just have to break down and get one of the Famous Test Kits from here!