The unit had to be calibrated right out of the box. No big deal I had bought ph calibrating solution. I tried the 7.0 solution and the meter read 6.8. I adjusted it like the directions said. I then tried it in test solution that was 4.0 and it was spot on. The reason for the 3 stars is when I opened the battery compartment to pull out the insulating strip the battery in the center was exploded. I took them out and a metal clip fell out too. I got that put back in and got some fresh batteries. It takes 3 batteries and there is no way they fit. All 3 fit in the compartment but there was so much space they could not begin to make contact. I had to jam a wad of aluminum foil into the space at the end of the row of batteries. The meter seems to work ok. But gee I really didn't think economy meant poor quality. It works but I really do not recommend this product.

Worked like a charm! Really glad to have it as sometimes I can't get the acid test to work right. I think the sodium hydroxide goes bad. Anyway this was good as a second look.

Years ago I bought a Milwaukee pH meter at the MoreBeer. I recently saw the Beverage Doctor pH meter so I ordered one thinking it would be easier to calibrate than my old meter. I followed the directions and mixed up the buffer solution for calibrating the Beverage Doctor meter and ordered new 7 pH solution for the test. I calibrated the Milwaukee meter using the 7 pH solution and calibrated the Beverage Doctor meter using their 4.0 pH solution following the instructions included with the instruments. After calibrating the Beverage Doctor meter I noticed it drifted even when sitting in the calibration solution. I then tested it in the 7 pH solution and it read low (6.8). I then rinsed it with RO water and tested it in the 4.0 solution again. It read 3.9. I did this several times between the two solutions and it continued to read off by 0.1 or 0.2. I tried calibrating the Beverage Doctor in the 7.0 pH solution but had the same results. The meter was still off slightly. I tested the Milwaukee meter in the 4.0 Beverage Doctor calibration solution and it was spot on 4.0. I then rinsed it with RO water and tested it in the 7 pH solution. Again it was spot on. I did this between the two solutions several times and it continued to read reliably. I've always stored my Milwaukee meter dry while the Beverage Doctor meter is stored wet. My preference is Milwaukee meter even though calibration is not as slick. I don't have to store it wet and it was more repeatable.

Overall I'm pretty satisfied with this meter. The switch is a little tight to turn on and it needs to be calibrated often. Make sure you get the PH calibration solution with this but its pretty easy to do and doesn't take long.

Perfect just what I needed to manage pH levels for brewing beer. Calibration could be easier other than that it worked great.