I've always known pool stores are a scam / black hole of sucking you in for way overpriced products which aren't really needed, well since properly managing my own pool for the first time recently, my experience of 'wow i would be poolstored if i didn't already know what i was doing by now' was going to a random pool shop just to get an alternative reading to try to see how accurate my own testing kits were, he took my sample and sloppily rushed around, sloshing around the stuff like a mad scientist, except not - more a bad scientist, because his test results for alkalinity and pH were way off (like alk 40 ppm lower than mine as well as another pool guy's test from the day before), and he was so confident about it too. My AT HOME checkers (about $400 worth of stuff) were clearly better than his junk...he didn't even know what borates or lanthanum chloride was...nuff said. Granted I think this was a particularly shoddy pool store, I've been to better ones before and since, but I still am finding the average pool store employee to know hardly anything about what they sell which is really weird why would they even work there? Anyway this guy probably would have got me to put so much bicarb in it would have made the pH go sky high.