I decided to purchase in spite of the low ratings, after reading how others had good results when following the instructions precisely. I figured: I can follow instructions precisely! ;-) My process: (1) run the jets of the hot tub for a few seconds to mix the water a bit, (2) scoop out a sample of water in measuring cup, (3) clean the reader window with the provided tool, (4) turn on the TruTest, strip in hand, press bottom button, (5) wait for countdown to say "dip", (6) dip for a second, then pull out, and shake off droplets (once only), (7) without sliding, insert strip into reader, aligning with top and making sure it lays flat, (8) do all this in the shade, and additionally cover the reader to keep external light from getting in (9) wait for readout I did this 5 times in a row, with the same sample of water. I also used 3 regular AquaChek Total Bromine strips for comparison, waiting for 15 seconds before letting my wife do the readout (I'm color blind). Results with red TruTest digital reader and matching red strips: (Total Bromine / pH / Total Alkalinity) 8.9 / 7.7 / 240 1.9 / 8.0 / 120 0.0 / 8.4 / 20 0.9 / 8.0 / 60 0.0 / 8.4 / 60 Results with AquaChek Total Bromine strips and "wife" analog reader: 1.0 / 8.0 /80 1.0 / 7.5 / 60 1.0 / 7.5 / 65 As you can see, the later results match up reasonably well between digital reader and my wife's readings: I should probably add some brom tabs, shock the hot tub, and use a small amount of "down" to get back to a lower pH level. After making those adjustments, I should also keep an eye on alkalinity, to see whether I need to increase it. But the first two results are WAY different from all the rest! Even if I'd done "best out of three" (wasting extra strips in the process), I still wouldn't have made the right decisions, based on those bromine and alkalinity readings! Now I'm torn. It would be nice not to have to wait for someone else to be available to read the strips for me, but if I can't use these digital readings with confidence, what's the point?
