Excellent advice and honest point of view, JamesCox. Thankyou for sharing this, and welcome to posting at TFP!To homeowners and pool managers: It's ok to go to the pool store if you know what YOU'RE doing, so you can tell if the person you're buying from knows what SHE'S/HE'S doing and isn't just trying to sell you chemicals. Any test can be off, especially if you're inconsistent about taking samples. I had a customer that was getting high CYA readings and was about to drain water off their pool, but it turned out they were taking samples from the very top of the pool!
In conclusion, I want to reiterate that I am selling you chemicals, and I can confirm that we are biased sources of information. Our information comes from our sales reps and blanket coverage recommendations from testing equipment companies, and even if you get a knowledgeable "veteran", there's still a good chance they will be biased. Learn how to check us!