My guess would be tester error--it's amazing that you can take the same water sample to 3 different stores and get 3 different test results. Actually, your test numbers are closer to consistent than they usually are! That's why we always recommend that you do your own testing--so you know you can trust your numbers. And if you're going to test your own water, you may as well get a comprehensive kit that tests for everything you need--hence the recommendation for the Taylor kit.

Either way, I see nothing wrong with your numbers that would prevent me swimming in the water, except that your chlorine still needs to come up a little bit.

Janet