Review on Revolutionary Digital Aid Pro: Ultimate Solution Powders for Professionals by Edward Perez

I bought this to use as an extra pH meter. This pH meter does not work. Never done. I have calibrated it many times. However, when I add it to water, I get a reading of 0000. That means it doesn't work. Forget that junk PH meter. Buy the pH meter from Dr. meters (yellow). That's just a few dollars more than the Digital Aid trash PH meter. I only had to calibrate my Dr.Meter ph meter once and after a year and a half it is still accurate.