I had been using calcium reagents from September of last year (stored in dark at room temperature), they started running low so I switched to the ones I bought new February this year. My calcium level went from 425 to 800. I'm using a speed stir and have ran the test a bunch of times, bottle completely vertical/etc. Had it tested at the pool store to confirm which one was correct and they came up with 440. So are my old reagents correct and new ones incorrect? Lost on what to do next. Thanks!