Some have had success with the checker test results. I'm not sold on the quality of the reagent. You clean tubes, try to get all of the reagant in the tube, test, retest and hope for the best. My primary issue is the checker reading a bit high compared to Salifert (~0.3 compared to zero on Salifert). But all and all, I like having a quick test that I don't have to hold in the light and try to determine the shade of very light blue. The checker is fairly easy to use and the results are more accurate than the color test in my opinion for the most part. I do keep Salifert around just to make sure on a monthly basis I'm running Ph free.
